LIBRARY OF CONGRESS, 



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UNITED STATES OF AMERICA. 



A SYNOPSIS 



OF 



JY^edical (jiemistry. 



A Brief Suggestive Consideration of the Practical 

Facts in Theoretical, Inorganic and Organic 

Chemistry, and in the Analysis of Poisons, 

with a Full Consideration of the 

Qualitative Analysis of Human 

and Animal Urine. 



FINLEY ELLINGWOOD, M. D. 

Professor of Medical Chemistry and Demonstrator of Analytical Chemistry in the 

Bennett Medical College: Professor and Demonstrator of Chemistry in the 

Chicago Veterinary College ; Editor of the Chicago Medical Times; 

Etc., Etc. 



CHICAGO. 
J. M. W. JONES STATIONERY & PRINTING CC 
76, 78, 80 AND 82 SHERMAN STREET, 




Entered According to Act of Congress, in the Year 1889, by 

FINLEY ELLINGWOOD, 

In the office of the Librarian of Congress, at Washington, D. C. 



PREFACE' 



During the past few years of my experience as a lecturer 
on Medical Chemistry, I have appreciated the difficulty exper- 
ienced by the larger proportion of medical students in obtain- 
ing, in the short time allotted to the study, from the mass 
of chemical literature of the day, the essential facts which will 
make the study of Medical Chemistry of practical value to them. 
Because of this difficulty, the entire subject is not understood, 
and many students leave College Tcnoiving nothing about Medical 
Chemistry. I believe that a little well learned and thoroughly 
comprehended, will be of infinitely greater practical value than 
the entire subject gone over and nothing understood. 

With this in mind, I have endeavored to arrange, in a sim- 
ple manner, devoid of technicalities, for my own classes, the 
essential facts, in a concise, compact form, in the order followed 
in my lectures, in which each topic is fully considered. The 
blank page is intended for the entry of notes by the student, 
in the course of the lectures, which shall assist his more perfect 
comprehension of the subject. 

I acknowledge my indebtedness to the literature of the 
present time, and especially to the following authors : Witt- 
haus, Fowne, Attfield, Barker, Bartley, Hoffmann and Ultz- 
mann, Draper, Harley, Lloyd, Clowes, "Wolff, Tyson, Worm- 
ley, etc. 

If other than my own students shall see any practical 
value in the arrangement I have here made, and can by this 
assistance the more easily comprehend this difficult subject, I 
shall be fully repaid. 

FlNLEY ELLINGWOOD. 
Chicago, October 1st, 1889. 



THEORETICAL CHEMISTRY. 



Chapter I. 

Science is a classified knowledge of nature, and is 
divided into two classes — natural science and physical 
science. 

Natural Science treats of the general structure and 
external appearance of nature. 

Physical Science treats of the properties and com- 
position of all matter. 

Chemistry is that branch of physical science which 
treats of the ultimate or atomic composition of bodies. 

Matter is anything cognizable by our physical senses. 

Physics and Chemistry both treat of the composi- 
tion of matter, but physics considers matter in the 
gross without recognizing changes which alter the abso- 
lute character of matter, while chemistry studies the 
most minute composition of matter, the character of its 
ultimate constituents and all the possible changes to 
which it may be subjected. 

Inorganic Chemistry studies the composition of 
inorganic or unorganized bodies. 

Organic Chemistry studies the composition of organ- 
ized bodies and their products. (Strictly, but illogically, 
it is the study of those substances containing carbon.) 

In the Study of Matter we will consider its divi- 
sions, attractions, indestructibility, weight and general 
states. 

Chemistry recognizes three divisions of matter — 
the mass, the molecule and the atom. 

The Mass is any portion of matter which may be 
appreciated by the senses. 

The Molecule is the smallest particle into which 
compound matter can be divided. 

The Atom is an ultimate particle of matter, the 
smallest subdivision possible. 



Two or more atoms compose a molecule, and any 
number of molecules make up a mass of matter. 

The Attractions of Matter are the forces which 
control all matter. These are gravitation, coJiesion and 
adhesion, and chemism. 

Gravitation is the law of attraction of masses of 
matter. 

Cohesion holds the molecules of a mass together 
when the molecules are alike, and adhesion when they 
are unlike. 

Chemism holds atoms together to form molecules. 

Matter is Indestructible. It changes its form, 
but the original constituents never change. 

Weight is the measurement of the force by which a 
body is attracted toward the center of the gravity of 
the earth. 

In chemistry, we consider three kinds of weight — 
absolute, apparent and specific weight. 

Absolute Weight is the weight of a substance 
unaffected by the atmosphere, the entire apparatus being 
in a vacuum. 

Apparent Weight is the usual weight, as deter- 
mined in the atmosphere by scales. 

Specific Weight or specific gravity is the com- 
parison of the weight of a given bulk of a substance 
with an equal bulk of some substance accepted as the 
standard of comparison. 

The General States in which matter may exist 
are three — solid, liquid and gas. 

In the solid form the cohesion between the molecules 
of matter is great, and the mass can be separated only 
with violence. 

In the liquid form the molecules are not firmly held 
together, but are capable of freer motion among them- 
selves. 

In the form of a gas, there is no attraction between 
the molecules of the matter, but a law of repulsion _ 
seems to exist which keeps the molecules apart. A gas 
is called an elastic fluid. It is easily compressed, and its 
density depends upon the amount of pressure to which 
it is subjected. 



CHEMICAL ELEMENTS. 



NAME. 




it 

2-1 


J' 9 ! 


if 




H. 

F. 
CI. 

B. 

I. 

Na. 
K. 
Li. 
Ag. 
Rb. 
Cs. 
Tl. 

O. 

s. 

Ca. 
Sr. 
Ba. 
Mg. 
Zn. 

Se- 
Se. 
Te. 
Cd. 
Gl. 
Yt. 
Ce. 
La. 
D. 
E. 
N. 
P. 
As. 
Sb. 
Au. 
Bi. 
B. 
Ga. 
C. 
Sn. 
Pb. 
Pt. 
Fe. 
Si. 
Al. 
Ti. 
Th. 
In. 
Pd. 
Zr. 
Cb. 
Ta. 
V. 
Mn. 
Cr. 
Ni. 
Co. 
Ur. 
Mo. 
Wo. 
Ru. 
Ro. 
Ir. 
Os. 
Ter. 
Sc. 


1 
19 
35 5 
80 
127 
23 

108 

85.5 
133 
204 

16 

32 

40 

87.5 
137 

24 

65 
200 

63.4 

79 
128 
112 

14 

92.5 
141 
139 
145 
166.5 

14 

31 

75 
120 
196 
210 

11 

70 

12 
118 
207 
197 

56 

28 

50 
231 
113 
106 

89.6 

94 
182 

50 

55 

52.5 

68 

59 
204 

96 
184 
104 
104 
197 
199 
148.5 

44 
173 


I. 

I. 
I. III. v. 
I. III. v. 

i. 
i. in. 

1. III. V. 

I. 
i. in. 

i. 

i. 
i. in. 

n. 

II. IV. VI. 

ii. 

II. IV. 

n. 
ii. 
ii. 

Hg2. II. 

II. 

II. IV. VI. 

II. IV. VI. 

II. 

n. 
u. 

II. IV. 

II. 
n. 
n. 

i. ni. v. 

III. v. 
III. v. 
III. v. 

ni. 

III. v. 

in. 
in. 

II. IV. 

II. IV. 
II. IV. 
II. IV. 
II. IV. 
II. IV. 

IV. VI. 
II. IV. 
II. IV. 

II. 

II. IV. 

II. IV. 
V. 
V. 

III. V. 
II. IV. VI. 
II. IV. VI. 
II. TV. VI 
II. IV. VI. 
II. IV. VI. 
II. IV. VI. 

IV. VI. 

ii. rv. vi. 

II. IV. VI. 

ii. rv. vi. 

II. IV. VI. 


+ 




Chlorine 


- 






Sodium {Natrium) 

Potassium (Kalimn ) 










Rubidium 




Thallium 






















Barium 


























+ 




Yttrium 


+ 
































1 

+ 




Boron 




Tin (Stannum) 




















+ 






14- 












1 
















+ 


Chromium 


Cobalt 


i 


Tungsten ( Wolfram) 


I 
t 
















Ytterbium 









Very many substances can be made to assume all of 
the states of matter, and to change backward and for- 
ward from a solid to a liquid and to a gas ; or from a gas 
to a liquid or solid. This is done by the application or 
abstraction of pressure, or by the application or abstrac- 
tion of heat. . 

An Element, or a simple substance, is one which 
cannot be subdivided into, or made to yield other sub- 

A Compound, or a compound substance, is one com- 
posed of the union of two or more elemental or simple 
substances. A compound may be made to change its 
character, and be resolved into two or more simple sub- 
stances. 

There are sixty-seven well-known elements. At our 
usual temperature and atmospheric pressure, five of 
these are gases (H. O. N. F. CI.); three are liquids 
(B. Hg. Ga.), and the remainder are solids. 

In the designation of the elements in chemical form- 
ulas certain symbols are used. The symbol is either the 
initial letter of the Latin name of the element, or the 
initial letter followed by a suggestive letter from the 



name. 



A Symbol stands for the name of the element. It 
also stands for one atom of the element ; for the weight 
of one atom, the atomic weight of the element ; and for 
one volume. ■ 

An Atom is a most minute portion of a body ; an 
indivisible particle of matter. 

Atoms differ in weight, and in the quantity and qual- 
ity of the power by which they unite with each other in 
forming molecules,, m . 

To all atoms are ascribed a definite relative weight. 

The Atomic Weight of an element is the compar- 
ative weight of a volume of the element, compared with 
the same quantity of hydrogen, which, being the light- 
est of all the elements, is taken as the standard of com- 
parison, and this comparative weight of the element 
given to an atom of the element is said to be the weight 
of the atom. _ 

When atoms unite to form molecules they obey the 
inherent law of their natures— the law of chemism; and 



they unite in definite proportions which, in given com- 
pounds, never vary. 

Atoms are believed to be always united in the torm 
of molecules. 

A Simple Molecule is a molecule in which the 
atoms are alike — an elemental molecule. 

A Compound Molecule is one in which the atoms 
are unlike. 

We have said that atoms differ in the quantity of the 
power with which they combine to form molecules. To 
illustrate : One atom of chlorine will combine with one 
atom of hydrogen, but one atom of oxygen will not 
combine with less than two atoms of hydrogen, and one 
atom of nitrogen demands three atoms of hydrogen, 
and one atom of carbon demands four atoms of hydro- 
gen. 

The Equivalence or combining power of an atom 
is the number of hydrogen atoms it would combine 
with, or be equal to. 

Atoms are called monads, or dyads, or triads, or tet- 
rads, or pentads, or hexads, or heptads, as they demand 
the equivalent of one, two, three, four, five, six or seven 
atoms of hydrogen. 

Some atoms vary in their combining powers, bul- 
phur and oxygen may unite with one of sulphur and one 
of oxygen, or one of sulphur and two of oxygen, 
or one of sulphur and three of oxygen— never more 
than three. Oxygen has two equivalences always. 
If that is true, then the variation is in the sulphur. 
When sulphur unites with one atom of oxygen, it has 
two equivalences like the oxygen. When it unites with 
two atoms of oxygen, it must have twice as many or four 
equivalences, and when with three of oxygen it must 
have six. 

The variation in equivalences always increases or 
diminishes by two. Thus an atom may combine with 
one or three or five equivalences ; or two or four or six. 
The equivalence of an atom is indicated by a Roman 
numeral placed above and to the right of the symbol. 

A Molecule is formed by the union of two or more 
atoms. It is the smallest particle into which compound 
matter can be divided and retain its identity. 



A Formula is the written representation of a mole- 
cule, or of a reaction between molecules. 

In Writing a Formula, the symbols of the constit- 
uent elements are written side by side, and if more than 
one atom is used, the number is placed a little below and 
to the right of the symbol. 

In multiplying molecules, the number of molecules to 
be considered may be placed just before the formula, or 
the formula may be enclosed in brackets and the number 
placed just below and to the right. 

A formula represents four things — the elements, the 
number of atoms, the volumes of the substance and the 
weight of the molecule — the molecular weight. 

A Simple Molecule is one in which the atoms are 
alike. It contains usually only two atoms, but there 
may be as many as six. 

A Compound Molecule is one in which the atoms 
are unlike. It may contain any number of atoms. 

There are two classes of compound molecules. 

Those in which the unlike atoms unite directly are 
called binary molecules, because, however many 
atoms there may be, they are of only two hinds. 

Those in which the unlike atoms are united by a 
third atom. These are called ternary molecules, be- 
cause there must be at least three kinds of atoms. 

Electricity is the only force which seems to influence 
the law of chemism. A current of electricity, passed 
through a liquid compound, or a solution of a com- 
pound, will cause the compound to decompose, and all 
the atoms of one element will go to the positive pole of 
the battery, and those of the other element will go to the 
negative pole. Those which go to the positive pole are 
called negative elements, and those that go to the 
negative pole are called positive elements. 

The elements of every compound molecule are united 
with reference to their electro-chemical character. 

An element, however, may be positive in one com- 
pound and negative in another. Its electro-chemism is 
not arbitrary. 

In a binary molecule (a molecule with two kinds of 
atoms) one of the elements will be positive to the other, 
which is negative. 



In Naming the Compounds, the name of the pos- 
itive element is written first, and the name of the nega- 
tive element, with the ending ide, is written second ; 
S"0" is the sulphur oxide. 

The equivalence is also considered in the name. If 
the elements combined are monads, then the name of 
the positive does not change. If they are combined in 
their highest equivalence, then the positive element ends 
with ic ; S^ 0" 3 is the sulphur^ oxide. If they are 
combined in their next to the highest equivalence, then 
the positive element will take the ending ous; S lv O" 2 is 
the sulphurous oxide. If there is a still lower combi- 
nation, the positive element takes the prefix hypo, and 
the suffix ous, also; S^O" is the hypo-sulphurous oxide. 
If there is a higher combination than the ic compound, 
the positive element takes the prefix per and the suffix ic. 
There are numerical prefixes attached sometimes, 
which also show the number of atoms. If one atom is 
used, the prefix is mon; if two, di; if three, tri; if 
four, tetr; if five, penta. 

In the Ternary Molecules, one element which is 
positive is united to another which is negative, by a 
third element, which acts as the linking or uniting element. 
The linking element will be found to exercise the 
same function in very many ternary compounds, as 
there are only a few which can exercise this function. 
The commonest of these are oxygen, sulphur, and nitro- 
gen, and the one which we will consider most is oxygen. 
A molecule of water is written H 2 ; graphically 
H-O-H. This type determines the structure of the ter- 
nary molecules. It is called the water type. 

The first class, called acids, are formed by the union 
of a negative element by oxygen to hydrogen, which is 
positive. 

The second, called bases, are formed by the union of 
an element which is positive by oxygen to hydrogen, 
which is negative. 

The third class, called salts, are formed by the union 
of a negative element by oxygen to a positive element. 
There is no hydrogen in a salt. 

Acid. Base. Salt. 

E-O-H E-O-H E-O-E 



An Acid is a sharp, sour substance which turns vege- 
table blues red. 

A Base — A basic substance, a hydrate, an alkali, is 
the opposite of an acid. It has a peculiar taste, and 
turns the red, produced by an acid, back to a blue. 

A Salt occupies a neutral position ; is not chemically 
active, and has no peculiar marked chemical properties. 
The union of an acid and a base will form a salt and water. 

All substances formed by the rule given for acids 
are acids; but all the substances known in chemistry to 
possess the properties of an acid, are not formed this 
way. There are a few substances which have a binary 
molecule, and yet have acid properties. 

In the Naming of Ternary Compounds, instead 
of the ide terminal of the binaries, the suffix ate or ite is 
used to designate that oxygen unites two other elements. 

If the elements are in their highest equivalence, the 
ending of the negative element is ate; if in their next 
lower equivalence, it is ite ; if lower yet, the prefix 
hypo is subjoined to the negative. If higher than the 
ate, it has the prefix per. 

The commonest method of naming is to follow the 
name of the characteristic element with the word acid 
or base, and determine its equivalence by the same 
suffixes as the binaries, ic or ous. 

To illustrate : Hydrogen, which is positive, may be 
united by oxygen to sulphur, which is negative. The 
negative element sulphur, taking the ending ate, gives 
the hydrogen sulphate, provided sulphur is in the equiva- 
lence of a hexad ; if it is next lower — a tetrad — the 
the compound would be hydrogen sulphite', if still lower, 
it would be the hydrogen hyposulphite. 

This compound is an acid. Considering sulphur as 
the characteristic element, the compound is a sulphur 
acid. In the highest equivalence of the sulphur, it is 
sulphuric acid ; in the next lower it is the sulphuiYWs 
acid ; and still lower the /lyposulphurous acid. 

In a careful study of all the ternary compounds, we 
find that all of them may be placed in a few classes, and 
that in each class there is a group of atoms which is 
present in every compound of that class. The groups 
of atoms are called radicals. 



A Radical is an atom or an unsaturated group of 
atoms, which is found present as characteristic of dis- 
tinct classes of compound molecules. 

A radical has one, two, three, or more unsatisfied 
bonds or equivalences like atoms, and is thus known as 
a monad, dyad or triad radical. 

The hydroxyl radical (HO)' forms the hydrates. The 
nitrosyl radical (N0 3 )' forms the nitrates. The am- 
monium radical (NH 4 )' forms the ammonium com- 
pounds. The chloryl radical (C10 3 )' forms the chlorates. 
The sulphuryl radical (S0 4 )" forms the sulphates. The 
carbonyl radical (CO s )" forms the carbonates. The chro- 
myl radical (Cr0 4 )" forms the chromates. The phos- 
phoryl radical (P0 4 )'" forms the phosphates. The 
cyanogen radical (CN)' forms the cyanides. 

If we closely observe the structure of bases, we ob- 
serve that they are compounds of the hydroxyl radical, 
and are thus called hydrates. 

There are a class of compounds which are the ano- 
logues of the acids, bases and salts, formed from the 
ammonium radical. These are called amides, amines 
and alkalamid.es, or ternary compounds, in which nitro- 
gen instead of oxygen is the linking element. 

An Amide is a compound in which a negative ele- 
ment is united by nitrogen to hydrogen, which is posi- 
tive. 

An Amine is a compound in which a positive ele- 
ment is united by nitrogen to hydrogen which is nega- 
tive. 

An Alkalamide is a compound in which a negative 
element is united by nitrogen to a positive element. 

I have said that each atom represents one volume, 
and each molecule represents two volumes. 

Ampere's Law. Ampere asserted that equal vol- 
umes of all substances in a state of gas must contain 
the same number of molecules. 

If this is true, all molecules must be of the same size ; 
and if all molecules are the same size, a molecule contain- 
ing one hundred atoms must have those atoms crowded 
into the same space as two atoms would fill, in a molecule 
containing only two. 

This fact accounts for the change of size or volume 



when certain substances change their chemical charac- 
ters ; and it also accounts for the change in the density 
or weight of the substances. 

If equal volumes of different substances contain the 
same number of molecules, and there is a difference in 
the weight of the separate molecules, there would be 
the same difference in the weight of the volumes. 

A molecule of hydrogen weighs one ; a molecule of 
nitrogen weighs 14 times as much ; one of oxygen 
weighs 16 times as much, and one of chlorine weights 
35.5 times as much. These facts being true, equal vol- 
umes of these substances must weigh in exactly the 
same proportions. 

It will be observed that the weight of these molecules 
and volumes correspond exactly with the atomic weights 
of the elements represented. 

The atomic weights of the separate elements in a 
compound represents the exact comparative weights of 
the substances in any quantity of the compound. 

The carbonate of calcium has this formula, CaC0 3 , 
that is, one atom of calcium, atomic weight, 40 ; one 
atom of carbon, atomic weight, 12, and three atoms of 
oxygen, each weighing 16, the three weighing 48. The 
molecule, then, weighs 404-124-48, or 100. That is 
one hundred times as much as one hydrogen atom. 

If we had 100 pounds of the carbonate of calcium 
the proportions would be exactly the same, i.e.: 40 lbs. 
of carbon, 12 lbs. of calcium, and 48 lbs. of oxygen. 

Changes taking place between chemical substances 
can be estimated exactly on the basis of their atomic 
weights. 

The following rules will determine the amount of any 
constituent of a compound in a given quantity of the 
compound : 

Rule. — Multiply the atomic weight of the unknown 
substance by the weight of the quantity, and divide 
that product by the molecular weight of the compound. 

By applying the above rule to each one of the con- 
stituents of a compound, the sum of the results should 
equal the total quantity. 

To determine the per cent, of any one constituent 
in the compound : Multiply the atomic weight of that 
n 



constituent by 100, and divide that product by the 
molecular weight of the compound. 

Knowing the percentage amounts of the constituents, 
to determine the amount of any constituent in a given 
quantity of the compound: Multiply the quantity by 
the percentage amount of the unknown constituent, and 
the product will be the amount of that constituent in 
the given quantity. 



INORGANIC CHEMISTRY. 



Chapter II. 

HYDROGEN. 

Symbol H', Atomic weight, 1. 
Hydrogen is an invisible, colorless, odorless, tasteless 
gas. It is the lightest substance known. It is 14.45 
times lighter than air, and 11,000 times lighter than 
water, 100 cubic inches weighs 2.15 grains. One grain 
measures 43.75 cubic inches. It is slightly soluble in 
water ; one and one-half volumes of the gas will dissolve 
in 100 volumes of water. Because of its lightness it is 
taken as the standard of density, atomic and molecular 
weight and volume. It is combustible and respirable, but 
will not support combustion or respiration. Heated 
with oxygen, they will unite with an explosion ; mixed 
with chlorine and exposed to strong sunlight, they will 
unite, otherwise it is not chemically active. A pressure 
of 650 atmospheres will reduce hydrogen to a liquid. 
Many metals will absorb hydrogen, notably palladium, 
one volume of which will take up 900 volumes of the 
gas. Graham maintained that under these circumstances, 
hydrogen is a metal, with a density of 2., and he called 
it hydrogenium. Hydrogen was known 300 years ago. 
It occurs in the exhalations of volcanoes, and composes 
the larger portion of the atmosphere of some of the 
fixed stars. The iron of Leonarto contains a large 
quantity of hydrogen gas. It exists in water, and in 
most organic substances, and in acid and basic substances. 
It can be obtained from water, by decomposing the 

12 



water with potassium, sodium or electricity, or with iron 
at a red heat, the oxygen of the water uniting with the 
elements used, form an oxide, and the hydrogen is set free. 
By acting on an acid with a metallic substance, hydrogen 
is set free, as: H 2 S0 4 +Zn=ZuS0. 1 +H 2 . Hydrogen, 
because of its lightness, was originally used to inflate 
balloons. In later years less expensive compound gases 
serve the purpose equally well. It is used in combus- 
tion to produce great heat. Hydrogen enters into very 
many compounds, which will be considered in their 
proper order. 

The Nascent State of an element named (from 
nascere, being born) is the condition of the atoms of the 
element at the inappreciable moment when they are 
neither united with atoms of their own or other kinds ; 
or the time between the moment of the liberation of the 
atoms from one compound, and their union to form any 
other compound. It is reasonable to suppose that their 
chemical energy, unsatisfied at just this brief moment, is 
in its full exercise, or that the energy is just the amount 
greater that would be necessary to decompose a satisfied 
molecule, once formed ; whether that be a simple mole- 
cule, or a compound molecule. 

OXYGEN. 

Symbol O". Atomic weight, 16. 

Oxygen is probably the most important of all 
chemical elements. It is a colorless, odorless, tasteless 
gas, 16 times heavier than hydrogen, 100 cubic inches 
weighs 34.25 grains. It is slightly soluble in water, 3 
volumes of oxygen in 100 volumes of water. Chemi- 
cally, it is very active. It is not combustible, but is 
the typical supporter of combustion. It unites directly 
with all elements, except fluorine, to form oxides. The 
union of oxygen with other substances, notably with 
carbon, accompanied with light and heat, is called 
combustion. It is the element which supports respira- 
tion. At a pressure of 300 atmospheres, and a temper- 
ature of — 220° Fah., it becomes a liquid. 

Oxygen was discovered in 1774 by Priestly; he called 
it dephlogisticated air. The following year Scheele dis- 
covered it and called it empyreal air. Lavosier gave it 



the name of oxygen, from two Greek words, signifying 
an ' ' acid former. " 

It is the most abundant element in nature. It com- 
poses eight-ninths of the weight of water, one-fifth of 
the air, three-fourths of the weight of animals, four- 
fifths of the weight of vegetables and one-half of the weight 
of minerals. In fact, it constitutes more than 65 per 
cent, of the globe. It unites to form compounds with 
every element except fluorine. 

Although so common in its occurrence, it is difficult 
to obtain free in large quantities. It may be obtained 
from the decomposition of water by electricity, and 
from the mercuric oxide by heat, or by heating the 
chlorate of potassium, facilitated by the presence of the 
black oxide of manganese. The reaction which takes 
place in the latter case is the following : (KC10 3 ) 2 + 
Heat, = (KC1) 3 + (0 2 ) 3 . One ounce of the chlorate 
will yield more than one gallon of oxygen gas. 

Oxygen is essential to animal life. It is inhaled into 
the lungs and, passing through the thin walls of the air 
vesicles by diffusion, enters directly into the blood, com- 
bines directly with the hsenioglobin, and oxidizes the 
waste products of the system within the circulation. 
One hundred volumes of the arterial blood in a dog con- 
tained twenty-two volumes of oxygen. It becomes a 
part of the tissues, and assists in the production of body 
heat. It stores up also the vital force in the food and 
imparts it to the animal. 

It is used in the arts to increase the intensity of com- 
bustion, in the production of great heat. 

OZONE AND ANTOZONE. 

Symbols (<9 3 ) and (O). 
Oxygen is a dyad under ordinary circumstances, and 
the molecule is composed of two atoms. It may exist 
under forced circumstances with three atoms in the 
molecule, or with only one atom in the molecule. In the 
former case it is called ozone, and in the latter, anto- 
zone ; or, active oxygen. The molecule of oxygen is be- 
lieved to be formed like this : 0~0. The molecule of 
ozone is formed like this: o<§, and that of antozone 
like this : 0> , (0 2 ) (0 3 ) and (O). If the density of a 



substance is equal to one-half of its molecular weight, 
then the density of oxygen is 16, the density of ozone is 
24 and that of antozone is 8. These substances exist in 
the air after a violent thunderstorm from the decompo- 
sition or rearrangement of the oxygen molecule by elec- 
tricity. Ozone is best known; it has a peculiar sul- 
phurous odor, and has a powerful purifying influence. 
It is an active disinfectant. It is concentrated oxygen. 

WATER. 

H 2 0. Di Hydrogen Oxide. 

Water is a stable liquid — limpid, mobile, odorless, 
colorless, tasteless, neutral — a poor conductor of heat, a 
better conductor of electricity. It is 773 times heavier 
than air, 11,143 times heavier than hydrogen. Within 
range of 180° Fah., it will exist in the three states of 
matter — a solid at and below 32°, a liquid between 32° 
and 212° and a vapor above 212°. 

There is a great change in volume between the liquid 
and gaseous forms, one volume of the former producing 
1,700 volumes of the latter. By the action of cold, 
water contracts to a point equal to 39 1-9° Fah.; below 
that it slowly expands. This is the point of maximum 
density of water. 

In 1781 Cavendish proved the composition of water, 
and in 1805 it was proved that one ounce of water was 
produced from 2,500 cubic inches of the mixed gases, 
hydrogen and oxygen, in the proportion of two volumes 
of the former to one of the latter. 

Water occurs abundantly in nature, free, and in com- 
bination. It may be formed synthetically, by burning 
together hydrogen and oxygen gases. 

In the economy of nature, water is most important. 
It is an almost universal solvent, and by this property it 
supplies nutrition to all life. Seven-eighths of the hu- 
man body is water. It is taken in by food, drink and 
respiration. It enters into the composition of rocks, 
and determines the crystallization of all crystalline bodies. 
HYDROGEN DI-OXIDE. • 

H % 2 . Free Hydroxyl. 
Hydrogen di-oxide; peroxide of hydrogen, or 
oxygenated water, is a colorless, syrupy liquid. It 



contains an excess of oxygen, and is thus a powerful 
oxidizer. It will not freeze at — 30° Fahrenheit, and in a 
vacuum it may be evaporated unchanged. It is very 
unstable, readily giving up an atom of oxygen from 
every molecule. Diluted with water, it is more per- 
manent. It bleaches all vegetable colors. 

It was discovered in 1818 by Thenard. It may be 
prepared by the action of hydro carbonic acid and the 
barium di-oxide with the reaction — Ba0 2 +H 2 (C0 3 )= 
Ba(C0 3 )+H 2 2 . 

This agent is a valuable therapeutic agent. In sur- 
gery it is an active disinfectant, prevents the formation 
of pus, and stimulates to healthy granulation. It is 
also used in the manufacture of oxygen gas in small 
quantities. 

NITROGEN. 

Symbol, iV x ~ III_v - Atomic weight, 11^. 

Nitrogen is a colorless, odorless, tasteless gas; 100 
cubic inches weighs 30.14 grains. It will not burn nor 
support combustion. It is respirable, but will not sup- 
port respiration. It is not poisonous. It is soluble 
in water, one volume of the gas to fifty volumes of 
water. In its elemental form it is chemically inactive, 
but its compounds are all violently active. 

It was discovered by Rutherford in 1774, and because 
it would not support life, he called it Azote. Afterward 
it was called Nitrogen, — the "nitre former." 

It composes four-fifths of the atmosphere, and is 
found free in the gases of the stomach and intestines. 
It is found in combination in vegetable and animal 
bodies, in ammonia, and in combination with alkalies 
in the earth. It may be freed from admixture with 
oxygen in the air by removing the oxygen by the oxida- 
tion of some metals and phosphorus. 

Nitrogen dilutes the oxygen in respiration, and facili- 
tates the functions of that important clement. It is an 
essential constituent of the animal economy, but is sup- 
plied principally through the food. It is not used in 
the arts. 

Its commonest compounds are ammonia and the am- 
monium compounds, NH 3 and (NH 4 )' and the oxides 
and acids of nitrogen, and it enters into all the nitrates. 



THE ATMOSPHERE. 

Air is the gaseous envelope which encircles the earth. 
It is a mixture of gases, and not a chemical combina- 
tion; yet it is very constant in its composition. 

The complex character of the air was discovered in 
1669 by Mayow. The quantity, or proportion of its 
constituents, was discovered in 1771 by Priestly. 

The air is composed of two free gases, oxygen and 
nitrogen, mixed with unvarying uniformity by the law 
of diffusion in the proportions of 20.93 parts of 
oxygen by volume or 23 parts by weight, and 79.07 
parts of nitrogen by volume or 77 parts by weight. 
In addition to these there is water vapor, and the 
nitrogen oxides, and carbonic acid gas, and ammonia, 
and ozone. And there is. also dust, sodium chloride,- 
spores, germs, animalcules, insects and eggs. 

The composition of the air is proved in three ways :_ 

1st. The gases are not present in proportion of their 
atomic weight. . 

2d. The gases can be mixed mechanically, and a 
perfect atmosphere produced. 

3d. Each of the gases dissolves in water according 
to its individual solubility, perfectly independent of the 
other. . 

The height of the air is not known, but is believed to 
be no less than 200 miles, with the greatest density 
nearest the earth, one half of the entire quantity being 
within 2i miles of the earth. Yet, notwithstanding the 
difference in density, there is no difference in the pro- 
portions of the ingredients. < ; 

It is impossible to name all the uses of the air. It is 
essential to respiration, and the support of all life, and 
is also essential to the laws which control the earth in 
itself. 

DIFFUSION. 

If the mouths of two jars containing different gases 
be brought together so that the gases are in contact, and 
allowed to remain at rest a given time, it will be found 
that there is a uniform mechanical admixture of the 
gases in each of the j ars. If a porous partition be placed 
between the two jars the result will be the same. This 
is called diffusion. 



Physics asserts that the molecules of all gases are 
ever in motion in straight lines, and as molecules differ 
in weight, the lighter ones must move correspondingly 
faster than the smaller ones to offer the same resistance 
to the outward medium of pressure. If this is true a 
lighter gas will diffuse itself more quickly than a heavier 

Graham's Law is that the velocity of diffusion of 
two gases is inversely proportional to the square roots 
of their densities. 

AMMONIA. 

N'"II\. 

Ammonia is an intensely pungent, irrespirable gas, 
colorless and transparent, does not burn or support com- 
bustion. It is alkline in its taste and in its reaction, and 
is called volatile alkali. It is about half as heavy as the 
air, and is very soluble in water. At the freezing point 
one volume of water will dissolve 1,150 volumes of 
ammonia, forming the well known aqua ammonia, or 
the ammonium hydrate. At a temperature of 40°, or 
under pressure of only 6.5 atmospheres, it is reduced to 
a colorless, mobile, unstable liquid. This liquid will 
solidify at —103° Fan., it volatilizes rapidly with the 
abstraction of heat. 

Ammonia was known to the old alchemists 600 years 
ao-o In 1TY4 Priestly separated it as a gas, and called 
if alkaline air, although Black had obtained it free in 

It is produced by the decomposition of organic matter 
containing nitrogen. It is given off in the decomposi- 
tion of animal urine, and in the burning of horn, hair 
or hides. It was first obtained from the distillation of 
camel's dung, near the temple of Jupiter Ammon in the 
Libyan desert. It is an important constituent of guano. 
Coal contains two per cent, of nitrogen, and when the 
coal is distilled in the production of illuminating gas, a 
strong ammoniacal liquor remains as a by-product, from 
which ammonia gas is now manufactured. 

Ammonia may be produced by acting upon nitric acid 
with zinc, with the following reaction (HN0 3 ) 9 +ZnV- 
(Zn"(N0 3 ).)4+(H,0) 3 +NH 3 . It may also be prepared by 
actin^ on muriate of ammonium— ammonium chloride, 



with quick lime (NH 4 )Cl) 2 +CaO=CaCl 2 +H 2 0+(NH 3 ) 2 . 
Ammonia is a powerful stimulant, and is a valuable 
therapeutic agent. The salts are used internally very 
freely. It is a powerful escharotic. In sufficient quan- 
tities it is violently poisonous. It is used in the arts for 
many important purposes. 

AMMONIUM COMPOUNDS. 

There is a large number of compounds which belong 
to the same family, and are found to contain in their 
chemical structure the group of atoms, or the radical 

(NH 4 y. 

These are called the ammonium compounds from the 
radical which is called the ammonium radical. No sub- 
stance has ever been isolated which was known to be 
free ammonium. Weyl claimed that he had obtained a 
substance with the formula (NH 4 ) 2 . Although never 
free it acts similar in all its compounds to the metals 
sodium and potassium. And its compounds are the 
analogues of the compounds of these metals. 

Ammonium Hydrate (NH 4 )HO, is the result of 
the action of water upon ammonia gas, NH 3 +H 2 0= 
(NH 4 )HO. It is an unstable, pungent, mobile liquid, 
giving off the vapor of ammonia. 

Ammonium Sulphate (NH 4 ) 2 (S0 4 ) is obtained by 
acting upon the ammoniacal liquor from gas works 
with sulphuric acid. It is a crystalline body, easily 
soluble in water. 

Ammonium Carbonate (NH 4 ) 2 C0 3 or sesqui-car- 
bonate is prepared by heating the carbonate of calcium 
and the chloride of ammonium together and condensing 
the volatilized product. It is a hard mass; translucent; 
and it gives off the characteristic odor of ammonia. It 
is unstable. 

Ammonium Nitrate (NH 4 )N0 3 is a crystalline 
body formed by the action of the ammonium hydrate 
upon nitric acid. It is readily soluble in water and 
melts at 300° Fah. 

Ammonium Chloride (NH 4 C1) — Muriate of am- 
monium or sal-ammoniac is a common ammonium salt. 
It is prepared by acting upon the ammoniacal liquor of 
gas works with hydrochloric acid and subliming the 

19 



evaporated product. Its crystallization is peculiar. It 
forms a fibrous tough mass with a pungent salty taste. 

Ammonium Bromide (NH 4 )Br. may be formed 
by the direct union of ammonia and hydrobromic acid. 
It is a granular powder, which alters its color on expos- 
ure to light. 

Ammonium Iodide (NH 4 )I, is a crystalline body, 
very deliquescent. It decomposes in the air giving out 
the odor of iodine. It is formed by the action of 
hydriodic acid and ammonia. 

HYPO NITROUS OXIDE. 

N % 0. Laughing Gas. 

Hypo Nitrous Oxide is the gas which was first 
used as an anaesthetic. It is a rather heavy gas, color- 
less and odorless, but with a sweetish taste. It is one 
and one-half times heavier than air. It is soluble in 
water — 100 volumes of water will dissolve 78 volumes 
of the gas. At a pressure of 30 atmospheres, and at 
zero of the thermometer, it becomes a colorless, mobile 
liquid, which, if dissolved in the bi-sulphide of carbon 
and evaporated in a vacuum, will produce the lowest 
known temperature — 220° Fahrenheit. It is a very 
unstable liquid, and explodes readily. This gas will 
sustain respiration and support combustion. 

Laughing gas was discovered by Priestly in 1776, 
and was used as an anaesthetic by Wells in 1846. 

It may be obtained by the distillation of the ammon- 
ium nitrate, with this reaction — (N0 3 XNH 4 ) 2 +Heat= 
(H 2 0) 4 +(N 2 0) 2 . 

Hypo nitrous oxide is used largely as an anaesthetic 
at the present time, in minor surgery, and in dentistry, 
when a transient effect is desired. It is used as an in- 
halant in pulmonary troubles, and in those cases de- 
manding more perfect aeration of the blood. 

NITRIC ACID. 

H(NO s ). Hydrogen Nitrate. 

Nitric acid, or aqua fortis, is one of the commonest 

and most useful of the acids. In its pure state it is a 

heavy, colorless, fuming liquid, with a specific gravity 

of 1.52. It boils at 187° Fah. and freezes at —40°. It 



is not a stable acid, but changes its character by beat or 
when exposed to the air. Jt acts violently upon all or- 
ganic substances, and upon metals, either alone or in 
their compounds. Its union with non-nitrogenous or- 
ganic substances, such as sugar, glycerine, and cotton 
forms explosive compounds. 

There are at least five varieties of nitric acid in com- 
merce and pharmacy : First — The pure acid, just de- 
scribed, marked C. P. (chemically pure). It must be 
kept in strong smoked glass bottles in the dark, the 
bottles always full, and stopped with glass stoppers, 
sealed with paraffine. Second — The Commercial Aqua 
Fortis, a yellowish, very impure liquid, too impure for 
chemistry or pharmacy. It may contain arsenic, iron, 
sulphuric, or hydrochloric acid, and the nitrogen oxides 
as impurities. It is also in two strengths: the single 
acid contains 39 per cent, of the strong acid, and the 
double acid contains 64 per cent. Third — The Fuming 
Nitric Acid, highly concentrated; more or less free from 
impurities. It is of a reddish yellow color, and is a 
powerful oxidant. Fourth — The U.S. P. Acid. It 
contains TO per cent, of the C. P. concentrated acid; is 
a valuable caustic and escharotic. Fifth — The Dilute 
U.S. P. Acid. It contains only 10 per cent, of the C. 
P. acid. The B. P. acid contains 17.44 per cent. 

Nitric acid may be prepared by the action of sul- 
phuric acid upon the nitrate of sodium, or potassium, in 
a glass retort. Na(N0 3 )+H 2 (S0 4 )=HNa(S0 4 )-f H(N0 3 ). 
The nitric acid is driven off by distillation. 

Nitric acid was known in the eighth century. Ray- 
mond Lully, in the eleventh century, described its com- 
position fully. 

It has many uses in the arts and manufactures, in 
medicine and chemistry. 

Nitric acid produces on animal tissues a characteristic 
yellowish discoloration, by which its action may be 
known. 

When a poisonous dose of any corrosive acid has been 
taken, neutralize at once by soap and water, or carbon- 
ate of magnesia in water, or lime water. Don't waste 
time with oils, and do not use the stomach pump, as 
perforation may occur. 

21 



THE HALOGENS. 

The four elements— fluorine, chlorine, bromine and 
iodine — when studied together, seem to exhibit a re- 
markable relationship. If anything positive is known 
of fluorine, it is a light gas ; chlorine is a heavy gas ; 
bromine a liquid, and iodine a solid. As there is an in- 
crease in their atomic weights, there is a decrease in 
their comparative chemical activity. Their specific grav- 
ity, freezing point and boiling point, rises as their 
atomic weights increase. They are electro-chemically neg- 
ative ; all have a characteristic odor, and are excellent 
disinfectants and bleaching agents. They all combine 
energetically with metals forming similarly constructed 
compounds, or isomorphous compounds, with the same 
element ; that is, crystallizing with the same peculiari- 
ties. Because of the resemblance in their sodium, potas- 
sium and other salts, they are called the halogens, or ' 'salt 
formers," and their salts are called the haloid salts. 

FLUORINE AND HYDROFLUORIC ACID. 

Symbol F. Atomic weight, 19. HF. 

Fluorine has not yet been isolated. It is always found 
in combination with calcium, silicon, aluminum or 
sodium. Its chemical activity is so great that it enters 
into direct union with the substance of the vessel in 
which it is received when liberated. The fluorides of 
calcium {fluor spar), sodium and aluminum (cryolite), 
and hydrofluoric acid, are well known. 

Hydrofluoric Acid is the congener of hydrobromic, 
hydrochloric and hydriodic acids. It is an intensely 
corrosive acid, attacking glass and all vessels containing 
silicon. Its fumes are dangerously irritating, and must 
not be inhaled. 

CHLORINE. 

Symbol CI. Atomic weight, 35.5. 
Chlorine is one of the heaviest of the gases. It is a 
greenish yellow, pungent, irritating, suffocating gas. It 
is irrespirable, and will neither burn nor support com- 
bustion under ordinary circumstances. It is soluble in 
water, one volume of which will dissolve three volumes 
of the gas, producing a quite stable liquid, chlorine 



water. It is 2.5 times heavier than air, and may be 
easily reduced to a liquid at a pressure of four atmos- 
pheres, producing a dark yellow unstable liquid. It is 
an active substance chemically, in its usual form, but if 
prepared in the dark, it is inactive or passive. It unites 
most readily with hydrogen, and to this is due the fact 
that it possesses powerful bleaching and disinfectant 
properties. It abstracts the hydrogen from the water 
present and sets the oxygen free, which is really the 
active agent. 

Chlorine was discovered by Scheele in 1774. He 
called it " dephlogisticated muriatic acid." In 1810, 
Sir Humphrey Davy established its elemental character, 
and named it chlorine, from the Greek word Chloros, 
green, because of its green color. It is never found free, 
but is very common in combination with sodium, potas- 
sium, magnesium and calcium. Every quart of sea 
water, because of the presence of these compounds, 
contains nearly five quarts of chlorine gas. 

Chlorine may be obtained by acting upon common 
salt, NaCl, and black oxide of manganese with sulphuric 
acid. This is the reaction : (NaCl) 2 +(H 2 (S0 4 )) 2 +Mn0 2 
=Mn(S0 4 )+Na 2 (S0 4 )+(H 2 0),+Cl 2 . It is collected in 
the bottom of an upright jar, by the upward displace- 
ment of air. It may also be obtained by the action of 
hydrochloric acid on the black oxide of manganese with 
this reaction : Mn0 2 +(HCl) 4 =MnCl 2 +(H 2 0) 2 +Cl 2 . 

. Chlorine is a powerful disinfectant, and many of its 
compounds are useful for that purpose. It destroys 
many organic coloring substances, thus acting as a pow- 
erful bleaching agent. 

HYDROCHLORIC ACID. 
HCl. 

Chlorine unites directly with hydrogen, forming a gas 
called hydrochloric acid gas. The old alchemists 
called this the spirit of sea salt. It is a colorless gas, 
with a pungent odor and a shaip acid taste. It fumes 
strongly in the air, is irrespirable, and injurious to veg- 
etation. It will neither burn, nor support combustion. 
It may be reduced to a liquid by a pressure of 40 atmos- 
pheres, at a temperature of — 50° Fan., which is the pure 

33 



acid, and is intensely corrosive. Glauber, in the 17th 
century, called this gas muriatic acid, from the Latin 
muria, or brine. Sir Humphrey Davy discovered its 
true composition in 1810. 

It is obtained by the action of sulphuric acid on com- 
mon salt, with this reaction : H 2 S04+(NaCl) 2 =Na^S0 4 

+(HCi) 2 . , ; t. 

The liquid hydrochloric acid of commerce and phar- 
macy is a solution of the gas in water. It is a colorless 
liquid when pure, with all the characteristic acid prop- 
erties of a strong mineral acid. The officinal hydro- 
chloric acid contains 31.9 per cent, of the gaseous acid, 
and has a specific gravity of 1.16. The dilute acid of 
the pharmacopcea contains only 10 per cent, of the gas. 

Hydrochloric acid is a valuable therapeutic agent, it 
is the free acid of the gastric juice, and is important in 
assisting digestion. It also has abundant uses in the 
arts. 

SODIUM CHLORIDE, 

NaCl. 

Common Salt is obtained from sea water, by allow- 
ing the water to evaporate in shallow vats or pans. The 
salt being easily crystallizable, crystallizes out of the 
concentrated liquid, and the mother liquor is poured off 
and the salt collected. Vast beds of rock salt, and 
mines of salt are found in various parts of the world. 

This substance has been long known. It is very sol- 
uble in water, and is used as a preservative of various 
substances. It is used in the arts and in manufactures. 
It is found in all plant life, and is present in every tissue 
and fluid of the animal body. 

BROMINE. 

Symbol Br. Atomic weight, 80. 
Bromine is a heavy, blood-red, fuming liquid. It 
has a strong, irritating, offensive, pungent odor, and is 
corrosive to animal tissues. It fames at all tempera- 
tures above its freezing point. It boils at 145.4° Fan., 
and freezes at —12°. It is slightly soluble in water, one 
part of bromine in 33 parts of water, at 60° Fah., is 
freely soluble in alcohol, chloroform, ether and the car- 
bon di-sulphide. It is similar to chlorine in its action, 



but is less active. It colors starch yellow, and precipi- 
tates silver from its solutions. 

It was discovered by Balard, in 1824, in sea water. 

It is not found free, but always in combination with 
the alkalies and magnesium in sea water and mineral 
springs. 

It is obtained from sea water. The water is evapor- 
ated until the more easily crystallizable salts are precip- 
itated. The mother liquor (Bittern) is then treated with 
sulphuric acid, and the black oxide of manganese, which 
sets chlorine free in the mixture, which, from its su- 
perior chemical activity, replaces the bromine, setting 
it free in the form of a vapor, which is conducted into 
a cooled receiver and condensed. 

Bromine is used quite freely in therapeutics, in its 
compounds, and as a disinfecting and decolorizing agent. 
It is used in photography. 

The common compounds of bromine are the hydro- 
bromic acid, HBr, and the bromides of sodium, 
potassium, and magnesium. 

HYDROGEN BROMIDE. 

HBr. Hydrobromic Acid. 
Hydrobromic Acid gas is colorless, fumes strongly 
in the air, is readily soluble in water, forming a solu- 
tion of the acid with properties similar to hydrochloric 

It is prepared by treating phosphorus under cold 
water with bromine, and distilling the liquid. Squibb 
prepares it by acting on a hot solution of bromide ot 
potassium with sulphuric acid. The reaction with the 
phosphorus in water is this: P4+(Br 2 )io==(-^^r 5 ) 4 i- 
(H 2 O) 18 =(H 3 PO 4 ) 4 +(HBr) 20 . 

The solution of hydrobromic acid gas in water pro- 
duces the liquid acid of pharmacy. It is a colorless 
liquid with the characteristic properties ot a mineral 
acid. The official acid contains about 10 per cent, ot 
the gas. . 

It is a useful medicine, acting more efficiently than 
any other of the bromides. It is a sedative and nerve 
tonic. 



IODINE. 

Symbol I. Atomic weight, 127. 

Iodine is a purplish black crystalline solid, very 
slightly soluble in water, one part dissolving in 7,000 
parts of the water. It is readily soluble in alcohol, 
ether, carbon disulphide and chloroform. It is the 
least active of the halogens. It is not an active poison, 
but destroys tissue and turns the skin yellow. It reacts 
readily with starch, forming the deep blue starch iodide. 
This reaction will detect the presence of iodine in 
300,000 parts of water. The di-sulphide of carbon 
will react upon iodine in a million parts of water, pro- 
ducing a peculiar purplish color. Iodine melts at 225° 
Fahrenheit and boils at 347°, gives off a purplish vapor 
and sublimes at all ordinary temperatures. 

It was discovered by Courtois in 1811 in the mother 
liquor of a solution of the ashes of seaweed, from 
which the soda salts had been precipitated by crystalli- 
zation. It received its name from its violet colored 
vapor. It is never found free, but always in combina- 
tion with an alkali or magnesium, in the ashes of sea 
weeds and in sea water. 

It is a valuable medicine, free and combined with 
metals and alkalies. It is used also in photography. 

The common compounds of iodine are the hydriodic 
acid, HI, the oxides and the iodides of potassium, 
sodium, magnesium, calcium and iron. 

HYDROGEN IODIDE. 

HI. Hydriodic Acid. 

Hydriodic Acid is a colorless gas with a strong 
acid reaction, and fumes in the air. It is easily con- 
densed into a liquid at a pressure of four atmospheres. 
It is as soluble as the hydrochloric acid gas in water, 
and its saturated solution gives the liquid (hydriodic) 
acid, which has a specific gravity of 1.7, boils at 2.60° 
Fahrenheit and contains 57 per cent, of the gaseous 
acid. 

The solution of the hydriodic acid gas in water yields 
a colorless liquid, with the characteristic properties of a 
mineral acid. It has a specific gravity of 1.7, and con- 
tains 57 per cent, of the gaseous acid. 



Hyclriodic acid is assuming an important place in 
medicine. It is used in the laboratory as a valuable 
chemical reagent in organic chemistry. 

ARSENIC. 

Symbol, As. IIL v - Atomic weight, 75. 

Arsenic is a heavy brittle solid of a dark steel gray 
color and a metallic lustre. It has two distinct allo- 
tropic modifications. One is the form just named, and 
the other is the amorphous variety, of a black color and 
a vitreous appearance. Arsenic volatilizes without fus- 
ing at 325° Fah. 

It has been known for centuries. It occurs native 
and in combination with other elements. Orpiment and 
realgar are sulphides of arsenic, and mispickle is a union 
of iron and arsenic. 

Arsenic is obtained by heating mispickle, or some of 
the sulphides of arsenic in retorts. The arsenic sub- 
limes and condenses in the cooler portions of the retort. 
It is also obtained by reducing the oxide by heating it 
with charcoal. 

Arsenic is used in the arts and pyrotechnics, and in 
the manufacture of shot and fly paper. 

The common compounds of arsenic are: The hydro- 
gen arsenide, AsH 3 ; the tri-sulphide, As 2 S 3 , or 
orpiment ; the oxides and acids of arsenic, As 2 3 , 
arsenious oxlde, and H 3 As 2 3 , the arsenious acid ; 
the arsenic oxide, As 2 5 , and the arsenic acid H 3 As0 4 , 
and potassium arsenide or Fowler's Solution. 

arsenious oxide. 

As 2 3 . Arsenious Acid. 
Arsenious Oxide, the tri-oxide of arsenic or white 
arsenic; the arsenic of the shops is a white crystalline, 
solid, ordinarily, but may also exist in an amorphous, 
vitreous form. It has a sweetish taste, afterward me- 
tallic, acrid, and nauseating. It has no odor, is slightly 
soluble in water — two parts of the crystals will dissolve 
in 1,000 parts of pure cold water, and 87 parts of the 
crystals in 1,000 parts of boiling water. The solution 
made with boiling water may be evaporated until the 
quantity is reduced about one-half, when 166.6 parts of 



arsenic will remain in perfect and permanent solution. 
Arsenious oxide occurs native as such. It occurs as 
a by-product where any ores are roasted which contain 
arsenic. It is so obtained for commercial and other 
purposes. The oxide sublimes and the first sublimate is 
purified by re-sublimation. 

Arsenious oxide is a valuable remedial agent, prop- 
erly used. It is an energetic corrosive poison. 

ANTIMONY. 

Stibium. Symbol Sb'. Atomic weight, 122. 

Antimony is a brittle crystalline solid of a bluish 
white color, resembling zinc. 

It occurs free in nature, and also in combination, 
principally with sulphur, to form a tri-sulphide, called 
stibnite. 

It is obtained by roasting the sulphide and fusing the 
product with charcoal. 

It is used in the manufacture of type metal and brit- 
tania. 

The common compounds of antimony are : hydrogen 

ANTIMONIDE, Sl/'TIg, the ANTIMONY CHLORIDE ; Sb^'Cls, 

the butter of antimony, the tri-sulphide, or sulphuret 
of antimony, and three oxides, the tri- oxide, Sb 2 3 , the 
pent-oxide, Sb 2 5 , and the tetr-oxide, Sb 2 4 ; tartar 
emetic is the antimonium and potassium tartrate, 
(KSbOC 4 H 4 (i ). It is prepared by boiling three parts of 
the tri-oxide of antimony with four parts of cream of 
tartar. The mixture is then filtered, the filtrate evaporated 
and the tartarized antimony crystallizes out. It is of 
considerable use in pharmacy and medicine, and is an 
active irritant poison to man. It is corrosive, and a 
powerful emetic. 

SULPHUR. 

Symbol S. n - IV - VL Atomic weight, 32. 
Sulphur in its commonest form is a lemon yellow solid; 
brittle, tasteless, odorless, and crystallizable ; insoluble 
in water, but soluble in the di-sulphide of carbon. It 
exists in three allotropic modifications, which include 
many forms. In the amorphous variety, there is the 
crude sulphur, and the roll sulphur or brimstone. In 
the crystalline variety, there is the flowers of sulphur, 



and precipitated or milk sulphur, and the last is the 
plastic form. Sulphur melts at 234° Fah. and boils at 
824°. It readily sublimes. It is purified by sublim- 
ation. 

Sulphur was known to the ancients. It is found free 
in the volcanic regions of Sicily and Italy. As iron 
pyeites it is found in Sweden, Norway, Spain and 
Portugal. It is found in all parts of the world com- 
bined with lead (galena), with zinc (blende), and in 
the sulphates. It is present in animal and vegetable 
tissues in considerable quantities. 

The sulphur of commerce is prepared usually from 
the free native sulphur, by sublimation. If the vapor is 
received in cold chambers, the product is the dry crystal- 
line flowers of sulphur ; if in hot chambers the product 
is in liquid form and is drawn off into moulds and cooled 
in the form of roll brimstone. 

Sulphur may be separated in the. same manner by 
heating any of the sulphides above named. Plastic 
sulphur is prepared by heating melted sulphur to 650° 
Fah., and then pouring it into cold water. It is soft, 
plastic, transparent, capable of being moulded like wax. 
It is not a permanent form, but may change back on 
exposure, to the yellow crystalline variety. 

Sulphur is used extensively in medicine. It is used 
in the arts, in the manufacture of sulphuric acid, and in 
the bleaching of woolen and straw goods. It is used 
in making matches, and in the manufacture of gun- 
powder. 

Sulphur unites readily with many elemental substances. 
The important compounds of sulphur are the mon-oxide 
(SO); the di-oxide (S0 2 ), and the tri-oxide (S0 8 ). 
The hydrogen sulphide (H 2 S), the sulphates, and the 

SULPHUR ACIDS. 

SULPHUROUS OXIDE. 

SO % . Anhydride. 
Sulphurous Oxide, the dioxide of sulphur, is a 
dense, colorless gas, twice as heavy as air, with the 
pungent suffocating odor of a burning match. It is 
quite soluble in water in the proportion of 40 volumes 
of the gas in one volume of water, forming sulphurous 



acid. Dissolved in alcohol it produces a colorless liquid, 
expansible by heat and very volatile, producing a great 
degree of cold (-85°) by its volatilization. It is neither 
combustible, nor a supporter of combustion. It is 
irrespirable, producing suffocation and exercising a 
corroding action on the lungs. 

Stahl first described the peculiar character of sulph- 
urous oxide; but Priestly, in 1774, was the first to 
carefully examine its properties. It is found abundantly 
in the exhalations from volcanoes. It is the direct 
product of the burning of sulphur in the air, or in 
oxygen, and is thus obtained. 

It is a useful compound. It is a powerfully disin- 
fectant and antiseptic agent, and is used for that pur- 
pose. It is a reducing agent, having a great attraction 
for oxygen. It is used for bleaching, decolorizing and 
deodorizing purposes. After colors are removed by 
this agent, they may be restored by the use of weak 
chlorine water, or an alkaline solution. United with 
water, the direct chemical product is sulphurous acid. 

HYDROGEN SULPHIDE. 

II^S. Sulphuretted Hydrogen. 

Hydrogen Sulphide is a heavy, colorless gas, with 
a stinking permanent odor and a disgusting taste. It 
is slightly acid in its reaction; is not irritating, but is 
poisonous. A dog will die in an atmosphere containing 
one part of the gas in 800 of the air. Birds die in one 
part in 1,000, and a man will die in one per cent, of 
the gas. It is narcotic in its action and deoxidizes the 
blood. It is soluble in the proportion of 3.23 volumes 
of the gas in one volume of water. A pressure of 17 
atmospheres will reduce it to a colorless liquid. It 
burns readily. 

Hydrogen Sulphide is the direct product of the de- 
composition of all animal matter and much vegetable 
matter. It is a large constituent of sewer gas, and is 
the cause of much disease in cities. It occurs in the 
animal body in certain diseases : by the decomposition 
of albumen in the intestines, in cancerous diseases, in 
abscesses, in phthisis, and in the bladder in cystitis. 



It is used almost only as a re-agent in the laboratory, 
as its reactions with the metals, producing sulphides, 
are characteristic and easily distinguishable. 

Its presence in the air may be detected by exposing 
a white paper wet with a solution of the lead nitrate. 
The paper becomes blackened. 

THE SULPHUR ACIDS. 

There are many acids formed by the action of water 
on the sulphur oxides which are very interesting. The 
common sulphur acids, with a series called the polythi- 
onic series, or the many sulphur series, from the 
repetition of the sulphur atoms in the molecule, is the 
following : 

H 2 S0 2 =Hyposulphurous acid. 

H 2 S0 3 =Sulphurous acid. 

H 2 S0 4 =Sulphuric acid. 

H 2 S 2 3 =Theo-sulphurous acid. 

H 2 S 2 0(i=Di-thionic acid. 

H 2 S 3 6 =Tri-thionic acid. 

Ho S 4 6 =Tetra-thionic acid. 

H 2 S 5 6 =Penta-thionic acid. 

H 2 S.>0 7 =Theo-sulphuric acid. 

By a careful study of this series we may understand 
how the replacement of the hydrogen in these com- 
pounds by some other element, will form the many com- 
pounds known as sulphates, sulphites or hyposulphites. 

HYDROGEN SULPHATE. 
H^SO^ Sulphuric Acid. 

Hydrogen Sulphate or sulphuric acid, oil of vit- 
riol, is perhaps the most important of all the acids 
known. It is a dense, colorless, oily, corrosive acid 
liquid, with a specific gravity of 1.S5. It has a strong 
attraction for water, and is used as a drying agent. It 
unites with water with extreme vigor, producing great 
heat. There are four varieties of sulphuric acid. 

1st. The commercial oil of vitriol, too impure for 
chemical or medicinal purposes — used only in manufact- 
ures. It has a brownish yellow color. 

2nd. The colorless pure acid, just described, marked 
C. P. — chemically pure. 



3rd. The glacial acid, which crystallizes at ordinary 
temperatures. 

4th. The dilute acid of the pharmacopcea, which 
contains only 9 or 10 per cent, of the strong acid. 

Su puuric acid was known in the 15th century. It 
occurs in the natural springs and in some rivers. In the 
process of its manufacture sulphur is burned in the air, 
and the product, S0 2 , is conducted into a lead chamber, 
which contains the higher nitrogen oxides and water 
vapor. Each molecule of the S0 2 immediately abstracts 
an atom of oxygen from the nitrogen oxides, and, unit- 
ing with a molecule of the water vapor, forms the acid. 
The nitrogen oxides which are reduced by the abstrac- 
tion of oxygen immediately replace their oxygen from 
the air. The acid thus quickly formed falls in the water 
in the bottom of the chamber, which is drawn off when 
it reaches a specific gravity of 1.45, and is reduced by 
evaporation to a specific gravity of 1.85, when it is 
transferred to carboys or tanks for shipment. The re- 
actions taking place in its formation are the following: 
S+0 2 =S0 2 +0=S0 3 +H 2 0=H 2 S0 4 . 

Sulphuric acid is the basis of chemical manufacture. 
It is used in the manufacture of citric, tartaric, and 
phosphoric acids — in the separation of the alkaloids, in 
the manufacture of the soda compounds, alum, phos- 
phorus, and many other chemical and pharmaceutical 
products. It is used in refining processes; in the puri- 
fication of petroleum and manufacture of fertilizers; in 
bleaching and dyeing, and in the manufacture of com- 
bustibles and explosives. It is used in therapeutics, but is 
not an important agent. The sulphates, however, which 
may be formed from it are very important medical agents. 

THEO-SULPHURIC ACID. 

II 2 S 2 0^. Di-SuJphur'tc Acid. 
Di-Sulphuric Acid, or the Nordhausen Acid, is a 
dark colored, intensely corrosive, fuming, concentrated 
heavy acid, having all the properties of the sulphuric 
acid intensified. It is prepared by the distillation of 
dried ferrous sulphate in Nordhausen, in Saxony, for the 
dissolving of indigo in the manufacture of the celebrated 
Saxony blues. It hisses in water, and is immediately 
destructive to animal tissues. Its uses are limited. 



PHOSPHORUS. 

Symbol P. IIL v - Atomic weight, 31. 

Phosphorus in its ordinary form is a translucent, 
wax-like, yellow solid ; luminous in the dark, unstable 
in the air. It is not soluble in water, but dissolves in 
alcohol, petroleum, ether, and the di-sulphide of carbon. 
It is violently poisonous, producing its effects by cleoxi- 
dation of the blood. It melts at 112°, boils at 554°, 
giving off a colorless vapor. Phosphorus is used in the 
manufacture of matches. It is an active therapeutic 
agent, but is too poisonous for common use. The acids 
of phosphorus and the phosphates and hypophosphites 
are common restoratives to the osseous and nervous 
structures of the system. 

Phosphorus may exist in two distinctly different allo- 
tropic states. The first is the form just described, and 
the second is the variety known as the red phosphorus. 
The red variety is insoluble in those solvents which will 
dissolve the other form. It has no odor, does not oxidize 
in the air, and is neither luminous nor poisonous. It is 
prepared by retaining the ordinary variety at a heat of 
500° for 36 hours. The heat destroys its affinity for 
oxygen. 

Phosphorus was discovered by Brandt in the product 
of evaporated urine, in 1669. It does not occur free, 
but is always found in combination, most often with 
calcium, sodium and potassium. It is derived from 
bones in which it exists as the tri-calcium phosphate. 

The ashes of burned bones are mixed with two-thirds 
their weight of strong sulphuric acid and 20 parts of 
water. This mixture stands 24 hours. The superna- 
tant liquid is poured off and evaporated to a syrupy 
consistency. This is mixed with 20 per cent, of its 
weight of powdered charcoal and sand, and heated to 
redness. When dry, the mass is heated in retorts to a 
white heat, when the phosphorus distills over and is 
condensed in receivers. The crude product is melted 
under water, and washed with a mixture of sulphuric 
acid and potassium bi-chromate for purification. The 
liquid product is moulded in sticks, in tubes cooled in 
water. It is kept in water for its proper preservation. 



POTASSIUM. 

Kalium. Symbol K. Atomic weight, 39. 

Potassium is a silver white or bluish white, lus- 
trous metal, which melts at 144° Fab.., the liquid hav- 
ing a little of the appearance of mercury. It distills at 
a red heat. It abstracts oxygen with great facility from 
the atmosphere and thus tarnishes quickly. It acts upon 
water, abstracting the oxygen and setting the hydrogen 
free, which may burn in the intense heat produced in 
its liberation. 

It is found in its compounds in various parts of the 
earth. It exists in animal and vegetable structures, in 
the soil and rocks and in the sea. It does not occur 
free. It was obtained free first by Sir Humphrey Davy, 
in 1807. It is obtained in the lye from a solution of 
wood ashes, and the hydrate, in this form, has been long 
used in making soap. 

It is prepared by heating together the potassium car- 
bonate and carbon. This, heated to a white heat with 
the potassium tartrate, drives off the free potassium by 
distillation, and is received and condensed under naph- 
tha. The process is difficult and dangerous. 

Its uses in its elemental state are limited, but it unites 
readily with many elements, forming the long list of po- 
tassium compounds which are of more or less import- 
ance in chemistry, in medicine and in the arts. 

The important compounds are its compounds with the 
halogens and the potassium hydrate, carbonate, nitrate, 
sulphate, and chromates. 

SODIUM. 

Natrium. Symbol Na. r - IIL Atomic weight, 23. 

Sodium resembles potassium in appearance. It is a 
soft, silver-white metal, lustrous and easily tarnished. 
It melts at 204° Fah., and volatilizes at a white heat, the 
vapor burning with a bright yellow flame. It abstracts 
oxygen from water, liberating the hydrogen, but not as 
actively as potassium. 

Davy obtained the metal free in 1807. In its com- 
pounds it is most abundant. It occurs in sea and rock 
salt, in borax, in nitrate of soda and in the carbonate 
and silicates. It is essential to all animal life. 



It is prepared in the same manner as potassium, from 
its carbonate. 

In its elemental form its use is limited to metallurgy. 
In its compounds, it is of extended importance in medi- 
cine, in arts and in manufactures. 

The important compounds of sodium are its halogen 
compounds, its carbonate, sulphate, hydrate, phosphate, 
and nitrate, and sulphite and hyposulphite. 

CALCIUM, 

Symbol Ca. UIV - Atomic weight, 4-0. 

Calcium is a brilliant light yellow, malleable and 
ductile metal, of the hardness of gold. It fuses at a 
red heat, and burns readily with a brilliant reddish-yel- 
low flame. It is permanent in dry air, but oxidizes 
quickly in moist air. 

It was obtained pure first in 1855 ; but its charac- 
ter was known to Davy in 1810. In its compounds it is 
a very widely distributed and an important element. All 
limestone, chalk and marble are calcium carbonate, and 
gypsum is calcium sulphate. 

It is prepared from fusing the calcium chloride or 
iodide with sodium or zinc, or by acting upon the melted 
chloride with electricity. Its important compounds are 
the calcium oxide, hydrate, chloride, sulphate, carbon- 
ate, phosphate and silicate. 

Its salts are very important in the animal economy. 
The phosphates are abundant in the bones and teeth, in 
the nervous structure, and, in fact, in every tissue and 
solid of the body. The phosphates remain in solution in 
the body fluids, unless those fluids become alkaline when 
they are precipitated in a white crystalline form. Alka- 
line urine is turbid, because the phosphates and carbon- 
ates of the lime are precipitated. The compounds of 
calcium are nearly all important therapeutic agents. 
They are of extended use in the manufactures and in the 
arts. 

MAGNESIUM. 

Symbol Mg. 11 - Atomic weight, 2 J/,. 
Magnesium is a tenacious, ductile, brilliant, silver- 
white metal with a specific gravity of 1.75. It melts at 
a low red heat, and distills at a white heat. It is per- 



manent in dry air, but will readily tarnish in moist air. 
It burns with a bluish-white, brilliant light. 

Magnesium is abundant in nature, but always in its 
compounds. It is obtained free by acting upon the 
fused chloride with electricity; and by fusing the chlor- 
ides of sodium and magnesium with sodium; afterward 
purified by distillation in hydrogen gas. 

The elemental magnesium is used to produce brilliant 
lights, mainly for photographic purposes. The com- 
pounds are important remedial agents, and are present 
in animal and vegetable structures. 

ALUMINUM. 

Symbol Al. n - Atomic weight, 27.5. 

Aluminum is a brilliant, silver-white metal ; mal- 
leable and ductile, susceptible of a high degree of polish. 
It does not readily tarnish in the air. It is similar to 
silver in many of its properties. Wohler first obtained 
the metal free in 1828. 

Aluminum is most widely distributed in nature. It 
occurs in mica, feldspar, slate, clays, and in crystalline 
rocks. 

It occurs in emery, in the ruby and sapphire. The 
process of its separation has recently been simplified, and, 
because of that fact, it is coming into very general use. 

It is obtained by melting the chloride or the double 
chloride of sodium and aluminum in a verbratory fur- 
nace. It is also obtained from other aluminum com- 
pounds. 

It is used in the arts where silver and nickel are used. 
It is only inferior to the first; and highly superior to the 
latter. Some of its compounds are of use in medicine. 

IRON. 

JBerrmn. Symbol Fe. ll - IV - VI - Atomic weight, 56. 

Iron is an element of the utmost utility to man. 
When pure, it is a soft, brilliant, silvery- white, crystal- 
line metal ; the most tenacious of all metals ; malleable 
and ductile. In dry air it is not affected, but oxidizes 
quickly in the presence of moisture. At a bright-red 
heat it will decompose water, forming the ferroso ferric 
oxide and setting the hydrogen free. 



It has been known during the history of man. It is 
iound free in some meteorites, but is commonest in vari- 
ous ores from which it is easily separated by heat. 

Its principal ores are the iron pyrites, micaceous or 
clay ores, oxides, carbonates, sulphates, arsenates, phos- 
phates and oxylates. 

The processes of its separation from its ores by heat 
are not complex, and are carried on, on a very extensive 
scale in many countries. 

Iron is the most common of all the metals. In man- 
ufacture, and in the arts, it is indispensable. In chem- 
istry, pharmacy and in medicine it is of great value. 

The chemical compounds of iron, most useful to the 
physician, are the chlorides, the oxides, the hydrates, 
the carbonates and the sulphates. 

LEAD. 

Plumbum. Ph. lliy - Atomic weight, 207. 

Lead is brilliant, bluish-white, very soft and malle- 
able. It fuses at a low heat, and is slightly volatile. It 
tarnishes very quickly in the air, and when heated oxi- 
dizes rapidly. 

Lead has been known for ages. It occurs in mines in 
England, Spain, America, and other countries. It is 
prepared from galena or the sulphide of lead by roast- 
ing the ore in a reverberatory furnace. 

It is widely used in manufactures and in the arts. Its 
use in medicine and chemistry are limited but important. 
Its compounds in any quantity in the animal economy 
are slowly poisonous. The common compounds are the 
man oxide, the tetroxide, the dioxide, the chlorides, 
iodides, nitrates, sulphates, and carbonates; the sul- 
phide, the acetate, and the chromate. 

COPPER. 

Cuprum. Symbol Cu. n - 1Y - Atomic weight, 63.5. 

Copper is a peculiar, reddish appearing metal— soft, 
ductile, and tenacious. It does not easily change in the 
air. It melts at 2200°, and is volatile. 

Copper has been long known. It was obtained by the 
Romans from Cyprus. It is now obtained from Sweden, 
China, Japan, and the Ural Mountains, but the largest 



mines in the world are on Lake Superior. It is found 
free and in combination with various substances. The 
methods of its separation are similar to those of iron and 
lead. 

Copper is extensively used in manufacture. It is used 
largely in alloy with zinc, tin, or nickel. It is used in 
chemistry and in medicine. Its common compounds are 
the chlorides, iodides, oxides, the sulphate, carbonate, 



ZINC. 

Symbol Zn. "■ Atomic weight, 65 

Zinc is a highly crystalline, bluish-white metal, not 
strongly cohesive. It is pulverizable at a temperature 
of 300° Fah; it is malleable and ductile, being easily 
rolled into sheets. It melts at 800° and volatilizes at 
1800°. It dissolves readily in dilute acids, decomposing 
them and liberating their hydrogen. 

The ancient Greeks used zinc abundantly in manu- 
facturing brass. It is now found in various parts of the 
world. Its ores are calamine (silicate), blende (sulphide), 
and smithsonite (carbonate). 

In its preparation the ore is heated in the air and the 
zinc oxidized. The oxide is heated to a white heat with 
charcoal, and the free zinc is distilled in proper re- 
ceivers. 

It is used extensively in architecture and to coat iron, 
because it does not easily oxidize. It is used as an ele- 
ment in the generation of electricity, and forms valua- 
ble alloys with copper, tin, and nickel. It has a limited 
use in medicine. Its common compounds are the 
oxide, carbonate, and sulphate. 

NICKEL. 

Symbol Ni. IL IV< Atomic weight, 59. 

Nickel is a pure, lustrous, silver-white malleable and 
ductile metal. It does not readily fuse, and is very te- 
nacious. It oxidizes in the air. 

It was discovered in 1751. It is obtained from the 
arsenide called Kupfernickel. It is difficult of separa- 
tion. It may be prepared from the oxalate or carbonate 
by fusing them with hydrogen gas. 



Nickel is used for coin and for making German silver, 
in which it is alloyed with copper and zinc. 

Its common compounds are the hydrate, chloride, sul- 
phate, oxide, and cyanide. 

Cobalt is closely allied to nickel, and is separated 
from its ores in the same manner. It has the same ap- 
pearance and the same atomic weight. 

TIN. 

Stannum Sn. ll - lY - Atomic weight, 118. 

Tin is a soft, white, crystallizable metal. It is not 
very tenacious or ductile, but quite malleable. It melts 
at 450 o Fah. Is not volatile. 

It was well known to the Ancients, and is mentioned 
in the Bible. Homer speaks of it, and Herodotus, 
because of the large quantities of it in the British Is- 
lands, called them the tin islands. 

It occurs native and also in combination. It is pre- 
pared for commerce similar to iron or lead. 

It is used extensively in the arts and in manufacture. 
It is alloyed with lead, copper, antimony and bismuth 
to form pewter, britannia, bell metal, gun metal, bronze, 
etc. It is not used in medicine. Its compounds are the 
chlorides, oxides and sulphides. 

SILVER. 

Argentwm Ag. L IIL Atomic weight, 108. 

Silver is a beautifully brilliant white metal, soft, yet 
harder than gold, with considerable tenacity, both 
malleable and ductile. It is an excellent conductor of 
both heat and electricity — perhaps the best known. It 
fuses at a high temperature, and is slightly volatile. It 
is not changed in the air at any temperature. 

It was well known to the Ancients. It occurs in its 
elemental form, and also in combination with sulphur, 
arsenic, antimony, copper and the halogens. It is found 
in South America, in Mexico, in the United States, in 
Hungary and Saxony. 

Silver is used in the arts, and its salts in medicine. 
Alloyed with ten per cent, of copper, it forms coin 
' silver. It is too soft to be used alone. 

Its compounds are the oxides, chlorides, Iromide and 
?, nitrate and 



GOLD. 

Aurum Au. I,m - Atomic weight, 196.6. 

Gold is an exceedingly brilliant, soft, orange-yellow 
metal. It is highly ductile, and extremely malleable. 
It is a good conductor of heat and electricity. It is 
permanent, unaffected by any single concentrated acid 
(insoluble). Hydrochloric and nitric acids combined 
(Aqua Regia) contain nascent chlorine, which, when the 
combined acids are brought in contact with gold, will 
act upon it, forming a solution of the chloride of gold. 

Gold is widely, although sparingly distributed over 
the earth's surface. It is found in strata of quartz, and 
in the alluvial sand from the disintegration of quartz 
rock It is easily extracted by quicksilver, which is 
driven off by distillation. 

Gold and silver, because of their intrinsic value, are 
used in the coinage of all nations. Gold is used for 
jewelry. It is too soft to be used alone, but is combined 
with silver and copper in alloy. Pure gold is said to be 
24 carats fine. Twenty-four parts of the alloy is said to 
be 1 J:, 18 or 20 carats fine, as it contains that many parts 
of pure gold and the remainder alloy. 

Gold is of no use in medicine uncombined. Its 
chloride, however, is a valuable therapeutic agent. 

The compounds of gold are the oxides and the chlor- 
ides, and the compound chloride of gold and sodium. 

PLATINUM. 

Symbol Ft. n - IV - Atomic weight, 198. 

Platinum is a rare, lustrous, silver-white metal; 
malleable, ductile, and very tenacious. It must be 
subjected to an intense heat (3218° Fah.) before fusing. 
It is not affected by the air or oxygen. It is a poor 
conductor of heat and electricity. Platinum possesses 
the peculiar property of condensing gases on its sur- 
face. In the form of a powder it will absorb 800 vol- 
umes of oxygen, and alcohol poured upon this alloy is 
spontaneously inflamed. 

Platinum exists in union with other elements and very 
rarely in a free state. It is found in North and South 
America, in Russia and Borneo. 



Platinum is used for making chemical vessels, because 
acids and powerful chemicals do not act upon it. It is 
used in the coinage of Eussia. Its only important com- 
pound is the tetrachloride (PtCL,). 

BISMUTH. 

* Symbol Bi. IIL v - Atomic weight, 210. 

Bismuth is a hard, brilliant metal with a bronze 
tint, quite brittle. It is not changed in the air, takes 
lire in a strong heat, and burns readily with a peculiar 
bluish-white flame. It has been known for 400 years. 
It occurs in the elemental form, and also as the sulphide 
oxide, and carbonate. The pure bismuth may be ob- 
tained by heating the nitrate with charcoal. 

Bismuth is used in the arts to form alloys, but the 
compounds only are used in medicine. 

The compounds are, the chloride (BiCl 3 ), the oxides 
(Bi 2 5 and Bi 2 O s ), and the hydrate (Bi(HO) 3 ), nitrate 
(Bi(N0 3 ) 8 , sulphate (Bi 2 (S0 4 ) 3 , carbonate and phosphate 
Bi(P0 4 ). Bismuth subnitrate is not a definite compound 
but rather a mixture. 

MERCURY. 

Symbol Hg. n . Quicksilver. Atomic weight, 200. 

Mercury is a liquid metal of a brilliant, silver- white 
color. It is volatile at a comparatively low tempera- 
ture. It boils at 680° Fah. , and freezes at —40°. It has 
only one atom in its molecule. It will form an amalgam, 
as its alloys are called, with all metals except iron. 

It has been well known for centuries, and is frequently 
mentioned by ancient writers. It occurs free in consid- 
erable quantities. It is found most abundantly in com- 
bination with sulphur as a sulphide (cinnibar). It is so 
found in Spain, in Austria and in California. The ore 
is heated in proper vessels, and the volatile product is 
conducted through cooled pipes or into a cooled cham- 
ber, where it condenses. Elemental mercury is of but 
little use in medicine. 

It is used for extracting gold and silver ores; and for 
amalgams. Its amalgam with tin is the common coating 
for mirrors. It is used in filling thermometers and in 
barometers, because of its susceptibility to changes of 



temperature, and the wide range between its freezing 
and boiling points. 

Its compounds, the chlorides and iodides, oxides and 
sulphates, are of use in medicine and surgery. All the 
salts of mercury are poisonous. 

MERCUROUS AND MERCURIC CHLORIDES. 

(Eg CI.),. HgCk. 

The Mild Chloride of Mercury, known as Calo- 
mel, the mercurous chloride, is a heavy white powder, in- 
soluble in water. It volatilizes at a low heat, and crystal- 
lizes in minute characteristic crystals. It is used quite ex- 
tensively in medicine. In sufficient doses it is poisonous. 

Corrosive Sublimate, the mercuric chloride or the 
corrosive chloride, contains double the amount of chlorine 
as the mild chloride, and is a powerful corrosive poison. 

It is soluble in both cold and hot water. It is pre- 
pared by distilling a mixture of common salt (NaCl) and 
the sulphate of mercury (HgS0 4 ). HgS0 4 +(NaCl) 2 = 
Na 2 S0 4 +HgCl 2 . Both the chlorides produce character- 
istic chemical reactions. 

Mercuric Iodide, Hgl 2 is a crystalline powder of a 
brilliant scarlet red color. It may be prepared by 
adding a solution of potassium iodide to a solution of a 
mercuric salt. It is volatile at a low heat. It has a 
limited use in medicine. 

Mercurous Iodide (Hgl) 2 has a more limited use 
even than the above. It is a greenish-yellow crystalline 
substance, and may be precipitated by acting upon a 
solution of any mercurous salt with iodine. 



ORGANIC CHEMISTRY. 



Chapter III. 

CARBON. 

Symbol C. IV - Atomic weight, 12. 
Carbon is one of the commonest of the elements. In 
the air at ordinary temperature, it is a permanent solid ; 
insoluble in all menstrua. It does not melt or volatalize. 
It occurs free in three distinct allotropic forms — the 
diamond, graphite and amorphous carbon. 



The Diamond is the hardest substance known. 
It is pure crystalline carbon, occurring in brilliant octa 
hedral crystals, usually colorless or yellowish — some- 
times blue, green, pink, brown or black. It is a poor 
conductor of heat and electricity. Heated intensely in 
a vacuum, it is converted into coke. It possesses a high 
power of refraction. 

Graphite is almost as pure carbon as the diamond. 
It is crystalline, of a dark gray color and a soft soapy 
feel. It does not burn readily, nor volatilize. It is the 
plumbago or black lead of commerce, and is used in the 
manufacture of lead pencils. 

There are several forms of amorphous carbon, both 
natural and artificial. The commonest of the natural 
forms is coal, the hardest of which, anthracite coal, may 
contain from 95 to 98 per cent, of carbon, but com- 
monly only from 80 to 90 per cent. The softer, or 
bituminous coal, ranges from cannel coal and jet down 
through several stages of decreasing hardness to the 
brown coal, lignite or wood coal. 

Of the artificial forms of amorphous carbon, the soot 
or lamp black, is quite pure carbon, and is prepared by 
the imperfect combustion of pitch, tarry substances or 
turpentine. 

It is used as a pigment. 

Charcoal is obtained by burning wood with an insuffici- 
ent supply of oxygen. It condenses gases and odorous sub ■ 
stances within its pores, and is thus an active disinfecting 
agent. It is used to prevent putrefaction and as a filtering 
agent, and also in the manufacture of gunpowder. 

Animal Charcoal is obtained by the incomplete com- 
bustion of animal substances, conducted in closed vessels. 
Bone black is made from bones, and ivory black from 
ivory. Bone black possesses a greater power of absorb- 
ing the coloring matter and putrid odor of substances 
filtered through it than wood charcoal. 

By treating bone black with dilute hydrochloric acid, 
the calcium phosphate which it contains is removed, and 
the product is the carbo animalis purijicatus. 

Coke is the cinder, or porous, hard, grayish substance 
which remains in gas retorts after the destructive distil 
lation of coal in the manufacture of illuminating gas. 



When iron retorts are used, there is deposited upon 
their walls a layer of hard, compact, grayish carbon, 
called gas retort carbon, which is an excellent conductor 
of electricity, and is used for the carbons or negative 
plates of galvanic batteries and for electric light points. 

CARBON MON OXIDE. 

CO. Carbonous Oxide. 

Carbon Mon Oxide is a colorless, tasteless gas, 
sparingly soluble in water and in alcohol. In the air it 
burns with oxygen, with a blue flame, producing the 
higher oxide of carbon, C0 2 . It is unstable in its chem- 
ical composition, the carbon being better satisfied in its 
highest equivalence. 

It is formed in any imperfect combustion where carbon 
is burned in an insufficient supply of oxygen. It may 
also be formed by passing the carbonic acid gas, C0 2 , 
over red hot charcoal, when it loses half of its oxygen. 

Carbonous oxide is a poisonous gas. Being given off 
readily from air tight hard-coal stoves and furnaces, and 
in the burning of illuminating gas, it is a common cause 
of vitiated atmosphere in tight rooms. 

Blast furnaces give off from 20 to 30 per cent, of 
this gas. One part of the gas in 200 of air will kill 
birds and small animals in a short time. Ordinary 
illuminating gas contains from 4 to 7 per cent, of this 
gas. A small quantity in a room produces languor, 
headache and debility. When inhaled it changes the 
character of the blood, preventing the corpuscles from 
carrying ©xygen to the tissues. Its effects are quite 
permanent. 

CARBON DI OXIDE. 

C0 2 . Carbonic Acid Gas. 
Carbon Di Oxide is the direct product of the burn- 
ing of carbon in the air. It may be produced also by 
the decomposition of the carbonates with hydrochloric 
or other mineral acids. It is a heavy, colorless, suffo- 
cating gas, with an acid taste. It neither burns nor 
supports combustion. It is soluble in equal volumes of 
water, at ordinary atmospheric pressure. Its solubility 
increases with increased pressure ; one volume for each 
additional atmosphere. Soda water is a solution of the 



gas in water under pressure. The gas may be reduced 
by the pressure of 38 atmospheres, at the freezing point 
of water, to a colorless liquid, which will evaporate on 
the removal of the pressure so rapidly as to freeze its 
own vapor. It does not burn or support combustion. 

This gas is an important permanent constituent of 
the atmosphere, in the proportion of about 4 parts in 
10,000. It is exhaled by man and animals, and is the 
product of all combustions and most decompositions of 
organic matter. It is absorbed by all vegetation, and 
is thus the source of the supply of carbon. Its absorp- 
tion takes place only by the influence of sunlight, there- 
fore there is a larger proportion found in the fields in 
the night than during the day. There is a larger pro- 
portion in the air of cities, because of the large quantity 
of carbon burned and the absence of vegetation to 
absorb the gas. It is estimated that a man 25 years old 
exhales about 550 quarts of the gas in 24 hours. If air 
contains more than 7 parts in 10,000 it is contaminated. 
If the gas is added to the air of a room without being 
formed in the air, the contamination is not so serious as 
when it is produced in the room by the combustion of 
the oxygen from the atmosphere of the room. In the 
latter case, the noxious gas is not only added to the 
atmosphere, but it is added at the expense of the oxygen 
of the same space. 

An animal will die quickly in a room containing one- 
fifth its volume of C0 2 if the gas was formed from the 
oxygen in the room, reducing the oxygen two parts per 
hundred of the atmosphere. But if there is more than 
the normal quantity of oxygen in the room, from 35 to 
40 parts per hundred, an animal will live a long time in 
a larger quantity of the gas. The poisonous effects of 
the gas are vertigo, drowsiness, headache, irritation in 
the larynx, increasing muscular weakness, and death 
from coma. 

The treatment of poisoning from carbonic acid gas 
consists in stimulation, artificial respiration, oxygen 
inhalations, electricity and friction. 

Carbon possesses to a greater degree than any other 
element the power of saturating its own equivalences. Be- 
cause of this fact, there are a great many compounds of 



carbon or organic substances. In the study of inor- 
ganic substances we have many compounds made up of 
many of the elements. There are many more organic 
substances than inorganic; but they are all made up of 
carbon, united with only a few other elements, princi- 
pally oxygen, hydrogen, and nitrogen, with different 
proportions of carbon. The change in the character of 
the molecules depends, not on a change in the kind of 
atoms, but on a change in the number of atoms, and in 
their relative position. 

ALCOHOL. 

(C. 2 & 5 )HO. Ethyl Hydrate. 

Vinic Alcohol, spirit of wine, ethylic alcohol, is a 
light, colorless, transparent, volatile liquid, with a sharp 
irritating taste and a spirituous odor. It is lighter than 
Avater, its specific gravity being only 0.80. It boils at 
173° Fah., and has never been frozen. It has a great 
affinity for water, mixing with it in all proportions. 

It attracts water from the air. It is an excellent 
solvent, dissolving many substances insoluble in water. 
Medicinal substances dissolved in alcohol are called 
tinctures. Gaseous and volatile substances so dissolved 
are called spirits. 

Fermentation is a decomposition, produced in the 
processes of the nutrition of certain low forms of ani- 
mal or vegetable life. The common ferments are the 
torula cerevisce, which produces alcoholic fermentation; 
the penicillium glcmcum, which produces lactic acid 
fermentation, and mycoderma acetic, which produces 
acetic acid fermentation or vinegar. 

Alcohol is the product of the fermentation of certain 
organic vegetable substances which contain sugar or 
starch; rye, barley, corn, rice, potatoes, the juices of 
certain fruits, and molasses, are fermented in the manu- 
facture of whisky, brandy, beer, ale, wines, rum, etc. 

Alcohol occurs in different strengths. 

Absolute alcohol is the pure alcohol without water or 
other foreign substance. It is rarely obtained. That 
which is purchased for absolute alcohol contains at least 
2 per cent, of water. Alcohol U. S. P. contains 94 per 
cent, of the absolute. 



It has a specific gravity of 0.82 The rectified spirit 
of wine, spiritus. rectificatus Br. P., contains 84 per cent, 
of absolute alcohol. 

Dilute alcohol, alcohol dilutum, U. S. P., contains 54 
per cent of the absolute. This is about the same as the 
proof spirit of commerce. 

Alcohol in sufficient doses is a powerful irritant poison. 
It abstracts water from the tissues and coagulates their 
albumenoids. Undiluted, it may produce immediate 
death. Diluted, its use may be prolonged; the poison- 
ous effects slowly appearing as its use is persisted in. 

It is an active stimulant, and produces temporary activ- 
ity of all the body functions, followed by a correspond- 
ing stage of depression. 

ACETIC ACID. 
C 2 E 4 2 . Pijroligneous Acid. 

Acetic Acid. Acetyl hydrate, or the hydrogen ace- 
tate, is a colorless, mobile liquid, with a pungent odor, 
and a sharp characteristic acid taste. When pure, it 
crystallizes at 62.6° Fah., and boils at 246°. Its spe- 
cific gravity is 1.08, at the freezing point of water. It 
mixes readily with water. It produces vesication and 
corrosive action on animal tissues. 

Acetic acid is produced by the destructive distillation 
of wood. The crude pyroligneous acid of commerce 
contains four per cent, of acetic acid and twenty per 
cent, of oily and tarry substances. This is distilled, 
and the distillate is acted upon in a complex process, by 
slacked lime, and the after product by sulphuric acid. 
The acetic acid is finally separated by distillation. 

The ordinary liquid acetic acid, U. S. P., contains 36 
per cent, of the pure acid dissolved in water. The pure, 
free acid is known as the glacial acetic acid. Acetic 
acid, in sufficient doses, is a corrosive poison. 

Vinegar is a liquid, acidulated with acetic acid ; 
produced therein by the ferment my coder ma aceti in the 
natural process of acetous fermentation. Alcoholic fer- 
mentation first takes place in the fermenting substance, 
and this is followed by the acetous fermentation, pro- 
duced artificially by the introduction of the character- 
istic ferment, or mother of vinegar. 



Vinegar is made from cider, wine and beer. It is 
necessary to add a small quantity of alcohol often dur- 
ing the fermenting process. 

ETHER. 

( C 2 H^2 0. Sulphuric Ether. 

Sulphuric Ether, the ethyl oxide, or ethylic ether, 
is a light, limpid, transparent, colorless liquid, with an 
intense unpleasant odor, and a sharp, acid, burning taste. 

Its specific gravity is 0-72, and its boiling point is 
only 94° Fah. It crystallizes at — 24° Fah. It is exceed- 
ingly volatile, and its vapor is highly inflammable and ex- 
plosive, mixed with air. It is soluble in water, and in 
alcohol. It is an excellent solvent of many substances, 
some not otherwise dissolved. 

Ether is made by the decomposition of alcohol with 
sulphuric acid. Five parts of the alcohol and nine parts 
of strong sulphuric acid are mixed in a vessel in a cold- 
water bath. This mixture, with a small stream of 
alcohol, is conducted into a retort heated in a sand-bath 
to 280° Fah. The chemical processes are such, that 
the sulphuric acid acts upon the alcohol, forming sul- 
phovinic acid and water. This newly formed organic 
acid, in its turn, acts upon another molecule of alcohol, 
forming ether and sulphuric acid. The following is the 
reaction which occurs: C 2 H 6 0+HoS0 4 =(C 2 H 6 )"S0 4 + 
H 2 0. (C,H 6 )"S0 4 +C 2 H 6 0=fC 2 H 5 ) 2 0+H,S0 4 . 

Ether is a common and comparatively safe general 
anaesthetic. It produces local anaesthesia, also, by the 
abstraction of heat. Internally, it is an active poison, 
although less so than chloroform. Death occurring 
more slowly, there is time for the administration of 
restoratives. 

Artificial respiration, and the application of electricity 
to the spinal centers and to the respiratory muscles, are 
the available means of restoration. 

CHLOROFORM. 

CHCl z . Dichloromethyl Chloride. 

Chloroform, formyl chloride, trichloromethane, is 

formed by the saturation of a common organic radical 

(CH)"' with chlorine. This is a derivative of the first 

of the paraffine series of hydro carbons; and the same 



radical similarly saturated with each of the halogens 
forms compounds similar in their construction to chloro- 
form, forming respectively jluroform, hromoform, and 
iodoform. 

Chloroform is a heavy, colorless, volatile liquid, with 
a pleasant etherial odor, and a sharp, pungent, sweet 
taste — soluble in alcohol and ether, but sparingly solu- 
ble in water. 

It will dissolve fats, resins, gutta-percha, certain alka- 
loids, phosphorus, iodine, and other substances insoluble 
in water or other solvents. 

It is stable in the light. 

It is prepared by heating together recently slacked 
lime, chloride of lime, and water, to which alcohol is 
added, and the temperature quickly raised. When the 
chloroform begins to distill over, the fire is withdrawn. 
The crude distillate is purified by exposure to sulphuric 
acid, and mixing this with alcohol and potassium car- 
bonate, and again distilling. 

Chloroform, taken internally in sufficient quantity, is 
an irritant poison. Being insoluble and easily diffus- 
ible, it produces intense local effects rapidly. 

Inhaled, it acts more quickly than other anaesthetics. 
It paralyzes the nerve centers, and thus immediately in- 
terferes with the functional workings of the important 
organs of the body, especially the heart. 

It produces more satisfactory results as an anaesthetic 
than ether, but, because of its speedy action, is more 
dangerous. 

There is no known antidote to chloroform. The 
patient may be quickly inverted. Nitrate of amyl, am- 
monia, hypodermic injections of nitro glycerine, and 
electricity, have all been beneficial, and all have failed. 

IODOFORM. 

CH1 Z . Di-iodomethyl Iodide. 
Iodoform, formyl iodide, tri-iodomethane, is a yellow 
crystalline solid, with a permanent penetrating odor and 
a sweetish taste. 96.7 per cent, of its weight is iodine. 
It sublimes, is insoluble in water and in the stronger 
acids and alkalies ; soluble in alcohol, ether, and in the 



essential oils and in the disulphide of carbon. It is pre- 
pared in much the same manner as chloroform. 

It is an active disinfectant and antiseptic, and is of 
extensive use in surgery. It is also given internally for 
gastric and intestinal disorders, with decomposition, or 
where an active antiseptic is needed. It may be given 
also in those cases where iodine is indicated. 

GLYCERIN. 

C z R 5 {IIO) z 

Glycerin is a syrupy liquid, colorless, odorless, with 
a sharp sweetish taste. Its specific gravity is 1.26. 
It is not crystallizable or easily volatile (crystals some- 
times form in glycerin, but the circumstances of their 
formation is not understood). It is soluble in water 
and in alcohol, and is itself a good solvent for many 
organic substances. 

Glycerin exists free in a number of vegetable oils. 
It occurs in alcoholic fermentation, and as a bi-product 
in the manufacture of stearin candles and soaps. It is 
prepared by the distillation in superheated steam of the 
product of the decomposition of neutral fats. 

Pure glycerin is valuable in medicine, It is a nu- 
trient, and will supply the place of cod liver oil with 
children. 

It is an antiseptic, and will prevent decomposition of 
food in the stomach and the consequent eructations of 
gas. It is valuable as an external application to bruises 
and abrasions of the skin and mucous membranes. 

CARBOLIC ACID 

C 6 R 6 O. Phenol. 

Carbolic Acid, phenol, phenic acid, hydrogen phe- 
nate is a crystalline solid with a peculiar, not unpleasant 
odor, and an acrid, caustic taste. 

It melts at 95° Fah. and boils at 370° Fah. It liquifies 
by the addition of about five per cent, of water at ordin- 
ary temperatures. It is not readily soluble in water, 
but is soluble in ether and in alcohol. It will not distill 
without decomposition. 

Carbolic acid is a coal tar product. In the distillation 
of coal tar, the distillate between 300° and 392° Fah. is 
treated with a solution of potassium hydrate. The 



crystalline product of this reaction is dissolved in hot 
water, and, becoming cool, the liquid separates in two 
layers. The heavier layer is neutralized with hydro- 
chloric acid ; the phenol separates ; is washed, dried 
with calcium chloride, and redistilled. The product of 
this redistillation is the crystalline carbolic acid. 

Carbolic acid is a powerful antiseptic. In contact 
with animal tissues, it produces a characteristic white 
discoloration and a cicatricial like contraction, and is an 
anaesthetic. It coagulates albumen. Taken internally 
in sufficient quantity, it is an energetic poison. It may 
be detected by the odor and by the white appearance 
of the membranes. If egg albumen be taken immedi- 
ately after the taking of carbolic acid, the excess of 
acid will unite with the albumen to form an insoluble 
albumenoid. In small doses, it is used as a medicine 
in cases where an antiseptic is needed, with decided 
beneficial effects. It also stimulates digestion and pro- 
motes the functions of the stomach in some cases of 
dyspepsia with fermentation. 

It is not as extensively used in surgery as formerly, 
although it is of extreme value as a surgical dressing. 



ANALYTIC AL CH EMISTRY. 

Chapter IV. 

The Laboratory Course in a medical college, be- 
cause of the limited time the student has to devote to it, 
is confined to a very limited portion of the entire work 
of analytical chemistry. It is confined to the study of 
simple water analysis, of a few reliable tests for common 
poisons and deleterious substances, whose presence is 
detrimental to health ; and to the analysis of urine, and 
perhaps other body fluids and excretory products. 
A thorough chemical course, however, is of great 
advantage. 

It is necessary also to precede the study of the tests, 
etc., by a short study of the laboratory apparatus, and 
manipulation or laboratory technics. 

Apparatus. — An alcohol lamp, an evaporating dish, 
a blow pipe, test tubes, tube rack, beaker-glass, glass- 



tubing, glass rods, watch glasses, platinum foil, a fun- 
nel, wash bottles, a tube brush, and filter-paper. 

A Solvent is the liquid which dissolves another sub- 
stance. 

Water is almost a universal solvent; other liquids are 
solvents to a certain extent. In chemistry, not only 
solids dissolve in liquids, but liquids dissolve heavier or 
lighter liquids or gases. 

A Simple Solution is the action between a solid 
and a liquid when brought into contact, by which the 
solid without change of its actual properties becomes 
also a liquid, and is uniformly diffused through the 
former liquid. 

A Chemical Solution is the action of a liquid 
upon a solid, reducing the solid to a liquid by changing 
the actual chemical characters of both the original solid 
and the liquid. 

Fusion is the conversion in an unchanged state into 
liquids by heat, (melting.) 

In strict accordance with the laws of chemistry, if 
two substances be brought together under proper cir- 
cumstances, the elements of which each is composed 
may act upon each other, or react; and changing their 
character produce other substances. This is a reac- 
tion. 

A Reagent is the chemical substance which is 
brought into contact with another to cause it to change 
its character. 

When one substance reacts upon another the product 
may be either solids, liquids or gases ; or solids and liq- 
uids and gases without regard to the physical character 
of the reagents. 

Eeactions take place readily between liquids and solu- 
tions of solids ; almost instantaneously between gases ; 
but very slowly, if at all, between solids, because free- 
dom of movement of the molecules, to bring them 
quickly in contact with each other, is essential to speedy 
chemical action. 

Bertholet's Law. If, when two substances in liq- 
uid form are brought together, a reaction takes place, 
forming a substance, solid and insoluble in the liquid 



present, that substance will form and separate as a pre- 
cipitate. 

If a gaseous body can form, it will form and escape 
as a gas or vapor. 

When a precipitate has settled in a vessel in which a 
reaction has taken place, it may be separated from the 
liquid, by decantation ox filtration of the liquid. 

Decantation is simply the pouring off of the super- 
natant liquid. It is sometimes employed alone, and 
sometimes before filtration. 

Filtration is the process of straining, and thus sep- 
arating the liquid from the solid. The filter is that 
through which the liquid is strained. It may be coarse, 
porous paper, muslin, asbestos, or glass wool — paper 
filters are most commonly used. 

After the liquid or filtrate has passed through the filter, 
if the solid or precipitate is desired, it may be washed by 
gently adding water until the water escapes clear. 

The precipitate may be removed from the filter by 
inverting the funnel containing it over an evaporating 
dish, and washing the filtrate with a fine stream of water 
into the dish; or a part of it may be removed by a glass 
rod; or the filter may be taken out of the funnel and 
spread over a drier and dried, and the precipitate re- 
moved when dried; or a hole may be punched through 
the bottom of the filter in the funnel and the precipitate 
washed through into a clean vessel. 

Evaporation is the conversion of a liquid into a 
vapor by heat ; the vapor escaping and thus exhausting 
the liquid. 

Distillation is the rapid evaporation of a liquid and 
its immediate re-conversion by cold to the liquid form 
(condensation). 

Sublimation is the conversion of a solid directly into 
a vapor by heat, and its immediate re-conversion into the 
solid form by cold. Only a few solids will sublime. 

Desiccation is the complete removal of water from 
a solid substance, either by heat or by exposure to some 
chemical substance which has a great affinity for water, 
as strong sulphuric acid. 

Incineration is the application of sufficient heat to 
a quantity of matter to remove all the volatile and 

53 



organic matter from the non-volatile and inorganic 
matter. 

GENERAL WORKING RULES. 

1. Keep everything on your table or shelves in per- 
fect order, always replacing everything immediately 
after using it. 

2. Keep the reagent bottles on the shelves in their 
numerical order with the labels outward. 

3. Always see that your reagent bottles are filled 
before you begin to work. 

4. In using liquid tests, hold the stopper of the bot- 
tle in the left hand (do not lay it down), and with the 
bottle in the right hand, 2?our out of the tack of the mouth 
of the bottle the very least quantity necessary to produce 
the reaction, pouring very slowly, or drop by drop. 

5. Use a separate portion of the substance you are 
testing at each test, unless directed otherwise. 

6. Follow your directions closely, literally, and if the 
results are not as expected, ask for an explanation. 

7. Never use any piece of apparatus unless it is per- 
fectly clean, and after working see that everything is 
clean and in its place before you leave. 

8. Write the results of the reactions obtained care- 
fully in your notes, using the formula? as previously 
instructed, being sure that the formula? are correctly 
written. 

9. In writing reactions, it is convenient to use the 
following abbreviations : 

Ppt. — Precipitate. Pt. or pts. — Part or parts. 

Sol. — Soluble. Sp.gr. — Specific gravity. 

Insol. — Insoluble. Gtt. — Drops. 

Soln. — Solution. P. E. — Equal parts. 

Dil. — Dilute. Con. — Concentrated. 

PRELIMINARY WORK. 

10. Dissolve some potassium nitrate in a little water 
in a test tube. The result is a simple solution. 

11. Put a small piece of marble (CaC0 3 ) into a 
tube, add a little water and boil. No change. Add five 
drops of hydrochloric acid. An effervescence occurs, a 
gas escapes. Result is a chemical solution. The reac- 
tion is (Ca // C0 3 )+2(HCl)=(Ca"Clo)+(H 2 0)+CO,. 



12. Dissolve some sulphate of copper in a little 
water in a tube. The result a simple solution. Pour 
the solution into the evaporating dish and slowly evap- 
orate. Result : the recovery of the original salt. 

13. Dissolve sodium carbonate in a test tube. Add 
hydrochloric acid. Pour into the evaporating dish and 
evaporate. Taste the salt recovered. Reaction Na 2 (C0 3 ) 
+2 (HCl=2(NaCl)+H 2 0+(C0 2 ). 

14. To a little water in a tube, add a little barium 
chloride solution. To this add five drops of sulphuric 
acid. A white precipitate quickly forms. Reaction : 
(Ba"CL,)+(H 2 (S0 4 )=(Ba / '(S0 4 +2(HCl). 

15. Decant the above liquid into another tube. Add 
a small piece of marble; effervescence. Reaction the 
same as number two. 

16. To a little water in a tube, add a little barium 
chloride solution, and to this add a little ammonium 
carbonate solution. Reaction : Ba"Cl 2 +2(NHj) (C0 3 )= 
(Ba"C0 3 )+2(NH 4 Cl). 

17. To a little dilute nitrate of silver solution add a 
little of the potassium iodide solution. Reaction : 
Ag(N0 3 )+KI=AgI-f-K(N0 3 ). 

Decant the supernatant liquid, and evaporate and 
recover the potassium nitrate salt. 

18. To the precipitate add a little strong sulphuric 
acid. Result : Change of color and violet vapors of 
iodine and hydriodic acid. 

19. To a little dilute nitrate of silver solution, add a 
few drops of hydrochloric acid, and study the appear- 
ance of the precipitate. Reaction : Ag(N0 3 )+HCl= 
AgCl+H(N0 3 ). 

20. To a little dilute sodium phosphate solution add 
a few drops of the nitrate of silver solution. Reaction: 
Na B (P0 4 )+3(Ag(NO a )=(Ag,(P0 4 )+3(Na(N0 8 ). 

21. Treat one-half the precipitate with aqua am- 
monia. It dissolves. Treat the other half with nitric 
acid. It dissolves. 

22. Dissolve some sulphate of copper in a tube. 
Add a few drops of sulphuric acid, and dip a pen-knife 
blade or piece of bright metal into it. Result : Free 
copper deposited on the blade. 



23. Cut glass tubing into lengths of about seven 
inches; draw out into sublimation tubes. 

24. Wash a piece of platinum foil, and ignite it in 
the flame until it no longer colors the flame yellow. 

25. Place a piece of marble on the foil, and heat it 
in the flame to a bright redness. It neither burns, 
blackens, nor disappears in a vapor — an inorganic, non- 
volatile body. 

26. Heat a piece of ammonium chloride on the foil. 
It disappears; volatizes without change of color — an in- 
organic volatile body. 

27. Heat a shaving of horn on the foil. It burns 
and blackens with the peculiar odor of burning hair. It 
contains carbon and nitrogen — an organic nitrogenized 
body. 

28. Heat a piece of starch on the foil. It burns and 
blackens without the odor of burning hair. It contains 
carbon but no nitrogen — an organic non-nitrogenized 
body. 

TOXICOLOGY. 

A poison is any substance which, after absorption into 
the blood, is capable of producing deleterious effects. 

A corrosive is a substance capable of producing 
deleterious effects by its chemical action upon the tissues, 
with which it comes in direct contact, without absorp- 
tion into the blood. 

Sources of evidence of poisoning are : Symp- 
toms — Post-mortem apj?ea?nnces and chemical analysis. 

In forming an opinion in a case of suspected poison- 
ing the medical examiner must acquaint himself with the 
special character of the symptoms, the previous health 
and habits of the patient, when fo6d or drink was last 
taken, whether any peculiar odor or taste was observed 
in the food, and whether others partook of the same. 

The investigation should be made in the presence of 
the proper law officer and one or more other physicians. 
All appearances should be carefully noted at the time 
of their observance, the length of the time the patient 
has been dead, how long he survived the first symptoms, 
and the external condition of the body. 



In the dissection, the condition of the entire alimen- 
tary canal and of all the organs essential to life should be 
minutely examined. g , 

The success or futility of the chemists' labors depend 
upon the knowledge and care of the physician during the 
post-mortem, which should, if possible, be conducted in 
the presence of the chemist who is to perform the analysis 
The stomach and intestines and their contents should 
be removed with both ends ligated. And, in addition, 
a portion of the liver, blood, one kidney, the spleen, 
heart the brain and a piece of muscle and the urine 
found in the bladder. The stomach and intestines 
should be placed in one vessel, the other organs, etc., 
in another, the brain in another, and the urine in a 
bottle These vessels must be of glass, and new and 
clean They must be sealed with glass stoppers or new 
corks securely tied and heavily coated with paraffine, 
to be opened only by the chemist who is to perform the 
analysis. 

STRYCHNINE. 

29 Strychnine is the alkaloid of the strychnos 
nux Vomica. It is a vegetable basic substance with an 
intensely bitter taste in aqueous solution, tne ^ A b ^ n g 
recognized in a solution containing one part in 600 000. 

30. Tests. Make a solution of the sulphate of 

s rye m » agte a drop of the dilute so i ut i on5 an d observe 

its persistent and intensely bitter taste. ...... 

32 Drop into the solution a minute crystal of the 
potassium bichromate. Observe the coloring—first blue, 
then violet, changing to rose pink, then to yellow. 

33 Dip a crystal of strychnia into a solution ol 
iodic acid in sulphuric acid. Observe the yellow color, 
changing to brick red, then to violet. 

34 Place a crystal of strychnia in a watch glass on 
white paper, and near it a small crystal of potassium bi- 
chromate, and drop on to each separately a drop of strong 
sulphuric acid. After a moment, carefully mix the two 
solutions. Observe the blue color, then violet, then red, 
then the entire fading of all color. 



35. If the most minute quantity of a strychnia solution 
be injected under the skin of a frog's back, it will quickly 
produce violent convulsions of a tetanic character. This 
is not absolutely reliable as other substances, and some- 
times only warm water will produce the same effect. 

36. One-sixth of a grain of strychnia is considered a 
fatal dose. The author has given one-seventh of a grain 
of the sulphate as an inter-muscular injection, in a severe 
case of hemiplegia, without unpleasant results. Severe 
tetanus has resulted from the use of one-tenth of a grain. 

37. The symptoms of poisoning by strychnia arc 
severe muscular contractions and lockjaw, following 
quickly after taking the medicine. It produces a sense 
of suffocation and thirst, and often vomiting, and con- 
traction of the pupils during the spasm. Death usually 
occurs within two hours. 

38. Treatment. Place the patient under the influ- 
ence of chloroform, if in convulsions, and quickly use 
the stomach pump. Wash out the stomach for a few 
times every five minutes with water containing pulver- 
ized charcoal in suspension, or with strong tea. Give 
full doses of chloral hydrate and the bromides. Gel- 
seminum, hypodermically, is of value. Morphine and 
camphor, and oxygen by inhalation, are active antidotes. 

MORPHINE. 

39. Morphine is one of the 18 alkaloids of opium, 
odorless and very bitter. Soluble, one part in 1,000 of 
cold water. 

40. Tests. Drop on to some crystals of morphia in 
a watch glass a few drops of strong nitric acid; an 
orange red color, changing to yellow is produced. 

41. Dissolve a small portion of the sulphate of 
morphia in water, and add a few drops of a neutral solu- 
tion of the chloride of iron ; a blue color is produced. 

42. Add to a solution of morphia a few drops of a 
solution of iodic acid, a yellow color is produced ; to this 
add a few drops of chloroform and shake violently. The 
chloroform will assume a deep violet color, and separate 
at the bottom. 



43. Mix a few crystals of morphine with cane sugar, 
and add a drop of strong sulphuric acid. A dark red 
color is produced. 

44. Chloride of gold, when mixed with a solution of 
the salts of morphia, gives a yellow precipitate, which 
turns violet blue. 

45. Morphia is a well-known active poison — more 
active with children than with adults. One grain, taken 
within six hours, has produced the death of an adult. 
The symptoms come on gradually, and death generally 
occurs within twelve hours, though often prolonged. 
The symptoms are profound stupor, contracted pupils, 
cyanosis, slow pulse and respiration. 

46. Treatment. If there is a probability that the 
poison is not all absorbed, wash out the stomach with a 
strong infusion of coffee or green tea. Give strong 
coffee freely, and hypodermatic injections of atropine in 
the earliest stages. Hot baths are of some service. 
Keep the patient moving. 

ATROPINE. 

C„HnNO s . 

47. Atropine is the alkaloid of the atropa bella- 
donna. It is a vegetable alkaline substance ; bitter, 
sparingly soluble, and volatilizes upon the boiling of its 
solutions. 

48. Tests. Dissolve a crystal of potassium bi-chro- 
mate in strong sulphuric acid ; add a crystal of atropine 
and a few drops of water ; observe the odor of orange 
blossoms. These two solutions remaining in contact 
for a few hours turn green. 

49. The colorless solution of atropine in sulphuric 
acid does not turn red by nitric acid, indicating the 
absence of morphia. 

50. . Add to a strong solution (50 per cent.) of mor- 
phine a five per cent, solution of corrosive sublimate. 
Observe the red precipitate. 

51. A few drops of a dilute solution of the salts of 
atropine dropped into one eye of a cat will quickly 
produce dilation of the pupil. Compare the two eyes. 

52. Atropine is an active and violent poison. A 



small fraction of a grain will produce death. It pro- 
duces dryness of the throat, dilation of the pupil, loss of 
speech, delirium, coma and death. 

53. Treatment. Evacuate the stomach, administer 
stimulants, give morphine hypodermically, and glycer- 
ine to overcome the sensation of strangling, produced 
by the extreme dryness of the throat. 

HYDROCYANIC ACID. 

{IICN) Hydrogen Cyanide. 

54. Hydrocyanic or Prussic Acid is a powerful 
organic acid. It is obtained from bitter almonds, peach 
and cherry pits, and from laurel water, and is found in 
the juice of the cassava. It can be formed by chemical 
processes, synthetically. 

55. Tests. — The characteristic odor of hydrocyanic 
acid, that of peach bloom, will assist in its detection. 

56. Drop into a solution of the acid a few drops of 
a solution of nitrate of silver. Observe the dense white 
precipitate which dissolves both in nitric acid and in a 
solution of potassium cyanide. 

57. To a solution of the acid add a solution of the 
ammonium sulphide. Evaporate this to dryness in a 
water bath, and add to the residue a solution of the fer- 
ric chloride. Observe the deep red color. 

58. To a solution of the acid add a few drops of a 
solution of picric acid. Heat the mixture; then cool it. 
Observe the deep red color. 

59. Dip a piece of filter paper into an alcoholic solu- 
tion of guaiacum, and then into a dilute solution of 
sulphate of copper. The vapor of hydrocyanic acid 
will turn this paper a deep blue. 

60. Hydrocyanic acid is a violent poison when either 
inhaled or taken internally. The anhydrous acid vapor 
will produce almost instant death to small animals. If 
enough is taken death occurs quickly. There is but 
little time to administer antidotes. 

61. Treatment. — The stomach pump should be 
used, artificial respiration, electricity, inhalations of am- 
monium, and cold affusion. If the patient does not die 
within an hour he may be saved. After death the body 
exhales a marked odor of the poison. 



62. When death is suspected from this poison, and 
an analysis is to be made, do not open the stomach until 
the analysis is to he begun. 

OXALIC ACID. 

63. Oxalic Acid is a crystalline, organic acid. It 
occurs as oxalates in the juices of many plants and trees, 
and as an excrete product in urine. It has an acid taste, 
and reddens litmus. 

64. Tests. — Neutralize a solution of the acid with 
a little ammonium hydrate; then add a solution of cal- 
cium chloride. Observe the white precipitate, which will 
dissolve in hydrochloric acid. 

65. Crystals heated with sulphuric acid decompose 
into gases CO and CO,, etc., and do not char 

66. To a solution of the acid add a few drops of 
barium chloride solution. Observe the white precipitate, 
soluble in hydrochloric; insoluble in acetic acid. 

67. To a solution of the acid add a few drops of a 
nitrate of silver solution. A white precipitate forms, 
soluble in nitric acid and in aqua ammonia. 

68. Oxalic acid is a violent poison. It acts as a cor- 
rosive and as a true poison. In dilute solutions it may 
produce death like a narcotic. In strong solutions it is 
corrosive. Death occurs quickly, generally within half 
an hour. 

69. Treatment. — Do not use the stomach pump. 
Neutralize with lime or magnesium (not the carbonates), 
in suspension in a little water. If no vomiting and no 
corrosion, after a time give emetics. 

ARSENIC. 

As. m - 75. 

70. Tests. Heat some crystals of the arsenious 
oxide in a sublimation tube. The substance disappears, 
and minute diamond-like crystals of the sublimate form 
on the walls of the tube above. 

71. Heat a portion of the metallic arsenic in a tube. 
The sublimate forms in zones— steel gray, black, and 
dirty gray. 

72. Break off the lower end of the last tube and 
heat again. Observe the diamond-like crystals of the 



sublimate of arsenious oxide, formed by the action of 
oxygen on the elementary arsenic. 

73. Drop some crystals of the oxide into a tube and 
on top of the crystals some minute charcoal chips. Heat 
the charcoal to redness, then heat the oxide. Observe 
the gray and black zones of elementary arsenic. The 
oxygen of the oxide has combined with the carbon of 
the charcoal, and set the arsenic free. 

74. Break off the point of this tube and heat the 
zones, and observe the white crystals of the sublimate 
of the oxide re-form on the tube above. 

75. Heat a small portion of paris green in a subli- 
mation tube. Observe the white diamond-like crystals 
of arsenious oxide form above. 

76. Place some paris green in another tube, and add 
chips of charcoal. Heat the charcoal, then the green. 
Observe the black zones of elementary arsenic. Break 
off the tip of the tube, and heat again, and observe the 
white crystals. 

77. Prepare a solution of arsenious oxide (As 2 8 ) 
by boiling. 

78. Take a little of the solution in the test tube, 
dilute it with equal parts of water. Add 20 drops of 
hydrochloric acid ; no result. It is necessary to acidu- 
late many solutions with hydrochloric acid before add- 
ing the hydrogen sulphide, or the sulphide of the metal 
will not precipitate. 

79. Add a solution of hydrogen sulphide freely to 
the mixture. Observe the yellow precipitate of the 
sulphide of arsenic. 

80. Warm this and allow the precipitate to separate 
and settle ; decant ; if necessary, filter. 

81. Place a little of the precipitate in each of two 
watch glasses. Add to one ammonium hydrate. It 
dissolves. Add to the other hydrochloric acid. It does 
not dissolve. 

82. Dry a portion of the precipitate, then mix it 
with twice as much potassium cyanide. Place it in a 
sublimation tube and heat. Observe the gray and black 
zones of the elementary arsenic. Break off the point 
of the tubes and heat the zones. Observe the white 
crystals of the arsenious oxide. 



83. Fill a small test tube half full of water; add 
two drops of ammonium hydrate. Then add drop by 
drop a solution of sulphate of copper until the precipi- 
tate no longer dissolves. To this add a little of the 
arsenic solution. Observe the green precipitate. Agitate, 
and allow to settle ; decant. Pour half of the precipi- 
tate into another tube ; add to one tube nitric acid 
(HN0 3 ) ; the precipitate dissolves in a colorless solution. 
Add to the other tube ammonium hydrate ; the precipi- 
tate dissolves in a deep blue solution. 

84. Prepare a solution of ammonium hydrate, as 
above, and add drop by drop a solution of nitrate of 
silver, instead of the sulphate of copper, in the same 
manner. To this, add the arsenic solution. Observe 
the canary yellow precipitate. Decant, and divide the 
precipitate into two portions. Treat one with nitric 
acid, and the other with ammonium hydrate. Observe 
the perfect colorless solution with both. 

85. Reinsch's Test. Boil narrow strips of bright 
copper foil in an arsenic solution, acidulated with hydro- 
chloric acid. The copper becomes gray, then black, 
from the deposit of arsenious oxide. If arsenic is in 
excess, it forms in scales. 

86. Remove the copper, dry it carefully with filter 
paper, place in a dry test tube and heat. Observe the 
white diamond-like crystals of the sublimate of the 
arsenious oxide. 

87. Arsenic has long been the most commonly used 
of all poisons for homicidal and suicidal purposes. Inas- 
much as it is easily detected, and produces a most pain- 
ful death, this fact is a peculiar one. If taken in large 
doses, its emetic effect sometimes produces immediate 
evacuation of the stomach, in man, and no permanently 
serious results accrue. 

88. Taken in small doses, persisted in and continued, 
the system can become habituated to it until a very large 
quantity may be taken without bad effect. 

89. The poisonous effects are those of an irritant to 
the intestinal tract and nervous system. From two 
grains of the oxide upward will produce death, which 
occurs within 24 hours. 



90. Treatment. If the case is seen immediately, 
the stomach pump may be used. If not, emesis may be 
produced by the sulphate of zinc in large quantities of 
warm water, or by the hypodermic injection of apomor- 
phia, T \ to -J of a grain. The chemical antidote must 
then be immediately administered. Dialized iron is 
very efficacious, given in doses of five grains for every 
grain of the arsenic salt. Or the hydrate of iron, in 
moist magma, quickly prepared by mixing the liquor 
ferri persulphate, or the tincture of the ferrous chloride, 
with one-third their bulk of aqua ammonia, and collect- 
ing the moist product on a muslin cloth ; wash it until 
all smell of ammonia is gone. Give teaspoonful doses 
every five minutes until at least 20 times as much as the 
arsenic salt is taken. 

ANTIMONY. 

Sb. m. 

91. As a poison, it acts upon man and carnivorous 
animals, but upon cattle and horses it has but little effect. 
In enormous doses persisted in, it produces emaciation 
and ultimately slow death. The tartar emetic is very 
violent in its effect on man. 

92. Tests. Prepare a solution of the tartar emetic 
(K(SbO)C 4 H 4 6 ) in water by heat, if necessary. 

93. Fill a tube one-fourth full of the solution. Add 
two drops of hydrochloric acid. A white precipitate 
forms (Sb 2 O s ) soluble in excess of the acid. 

94. Add a solution of hydrogen sulphide freely to 
this mixture. Observe the heavy orange red precipitate 
of the ammonium sulphide, and distinguish between 
this and the sulphide of arsenic. 

95. Decant and separate the precipitate into two 
parts. Add to one part ammonium hydrate. It does 
not dissolve. 

Add hydrochloric acid to the other portion. It dis- 
solves if slightly warmed. 

96. Reinsch's Test. Boil narrow strips of copper 
foil in the solution acidulated. Observe the bluish 
gray, purple, or violet deposit. Heated in a sublimation 
tube, the sublimate is amorphous, not crystalline, and 
deposits close to the slips. 



97. Antimony is an irritant in its poisonous effects. 
Two grains has produced death in an adult man. Ten 
grains is the poisonous dose. Death occurs in from 
four to six hours. 

98. Treatment. The stomach must be evacuated, 
large quantities of warm water being used. Strong 
decoctions of vegetable astringents, as oak bark, tannin, 
nutgalls or green tea, are then given. 

LEAD. 

PI. 207. 

99. Poisoning by lead is apt to occur accidentally 
from the varied uses of the substance. 

The oxides, nitrates or carbonates are most likely to 
be the salts used. 

100. Tests. Prepare a solution of the acetate or 
nitrate of lead in water. 

101. Fill a test tube one-fourth full of the solution ; 
add two drops of hydrochloric acid. Observe the white 
precipitate (PbCL) soluble in excess of water. 

102. Add a solution of the hydrogen sulphide freely 
to this mixture. Observe the brownish black precipi- 
tate ; distinctively colored at first (PbS). 

103. Collect the precipitate and divide it into two 
parts. Add to one part strong nitric acid, warm. The 
black sulphide is changed to the white sulphate (PbS0 4 ). 

104. Add to the other part dilute nitric acid, and 
boil. The precipitate dissolves. 

105. To a portion of the original solution add a few 
drops of the potassium iodide solution. Observe the 
deep yellow precipitate (PbL) solution. 

106. To a portion of the solution add a small quan- 
tity of the potassium bi-chromate solution. Observe the 
yellow precipitate. Add potassium hydrate solution; 
the precipitate dissolves. 

107. Lead poisoning is most commonly of a chronic 
character. It is induced in man and animals by taking 
the lead in slowly with food or drink. Man is poisoned 
by the frequent handling of lead substances, and animals 
have been slowly poisoned by eating grass near smelting 
works where the soot from the w r orks was deposited on 
the grass. It acts upon the nervous system. Death 
does not often occur quickly. 

65 



108. Treatment. In acute poisoning the sulphates 
of soda or magnesium may be given freely after evacua- 
tion of the stomach. In chronic poisoning the iodide of 
potassium is of value; and the water drank may be per- 
sistently acidulated with sulphuric acid. 

MERCURY. 

Eg. WO. 

109. In these tests we use the two chlorides of mer- 
cury. There are some differences in their reactions. 

THE OUS REACTIONS. THE IC REACTIONS. 

110. Heat a little cal- Heat a little corrosive 
omel in a sublimation tube. sublimate in a tube. It 



It turns yellow; does not 
fuse; it sublimes. 

111. Suspend a little 
calomel in water; it does 
not dissolve. 

112. To a little of the 
above mixture add a few 
drops of hydrochloric acid. 
No result. 

113. To the acidulated 
mixture add a solution of 
hydrogen sulphide in ex- 
cess. Observe the black 
precipitate immediately 
formed and colored. 



114. To a little of the 
mixture add a little aqua 
calcis. Observe the black 
precipitate. 

115. Add to the mixture 
a little potassium hydrate 
solution. Observe the 
black precipitate (Hg.,0). 

116. 



turns yellow, fuses, and 
sublimes. 

Prepare a solution of the 
corrosive sublimate. 

Fill a test tube one fourth 
full of the sublimate solu- 
tion. Add a few drops of 
hydrochloric acid. No re- 
sult. 

Fill the tube with the 
solution of hydrogen sul- 
phide. Observe the white, 
light yellow, dark yellow, 
light brown, dark brown, 
to black shading, gradually 
formed, and gradually deep- 
ening to the black. 

To a little of the solution 
add a little aqua calcis. 
Observe the yellow pre- 
cipitate. 

Add to the solution po- 
tassium hydrate. Observe 
the red precipitate (HgO). 

Add to the solution a 
little of the potassium io- 
dide solution. Observe the 
yellow to red precipitate. 



117. Treat the sulphide of either of the chlorides 
with nitric acid. They are partially soluble. They are 
soluble in equal parts of nitric and hydrochloric acids. 

118. Reinsch's Test, performed as with arsenic 
and antimony, produces a silver-gray coating on the 
copper. 

Dry and heat in a sublimation tube; the mercury sub- 
limes on the sides, and at the bottom of the tube in 
minute coalcscent globules of free mercury — quicksilver. 

119. Dip a piece of copper or gold in a solution of 
the corrosive sublimate, and rub the surface through the 
solution with the point of a knife blade. The mercury 
is deposited on the metallic surface. 

120. The salts of mercury are active poisons, and 
recently many deaths have resulted from using the cor- 
rosive sublimate as an antiseptic. Taken in sufficient 
quantity, it produces effects similar to arsenic poisoning, 
except that the effects begin and terminate more quickly. 

121. Treatment. Administer the white of an egg, 
and after a few minutes evacuate the stomach ; then 
administer another egg and again evacuate the stomach. 
In cases of slow, or chronic poisoning, the iodides of 
sodium or potassium should be given for a long time. 

PHOSPHORUS. 

P. 31. 

122. Tests. It may be known by its peculiar gar- 
licky odor, and by its luminosity in the dark. 

123. Boil a little starch in some water in a test tube; 
to this add as much potassium iodide as the starch. 
Saturate a piece of filter paper with this double solu- 
tion. This paper, exposed moist to the vapor of phos- 
phorus, is turned blue. 

124. Phosphorus acts as an acute, and as a chronic 
poison. It is also a poisonous escharotic. Children are 
poisoned from match heads. It kills by depriving the 
blood of its oxygen, and death occurs quickly where suffi- 
cient has been taken. 

125. Treatment. There is no known chemical 
antidote. Evacuate the stomach, and administer an old 
oil of turpentine. Avoid all fixed oils or fats. The 
calcium and magnesium carbonates in solutions or sus- 
pensions are thought to be of advantage. 



WATER. 
IL,0. 

Water, because of possible impurities in suspension 
or in solution, may be the cause of disease and death. 

The clearness of water is not an indication of its 
purity. Rain water may be found to contain on evapo- 
ration 40 parts of residue. 

The water of shallow wells is apt to contain much 
impure organic matter in solution. The application 
of a few simple tests will determine the presence of 
impurities. 

Tests. Fill a large bottle half full of water ; shake 
thoroughly, and smell. If there is any odor, there is 
an excess of impurities. 

Evaporate 8 or 10 ounces of water, and observe if 
any odor is present. The amount of odor is in propor- 
tion to the quantity of organic impurities, and, if present, 
there will be a black residue on complete evaporation. 

Weigh the dish and residue; then heat until the black 
residue is converted into a white ash ; weigh again, and 
the difference in the two weights will be the amount of 
organic matter in the quantity of water used. 

Take a definite quantity of water and strongly acidu- 
late with concentrated sulphuric acid. Add to this, 
from a burette over white paper, a known solution of 
potassium permanganate. When the salt solution ceases 
to be decolorized in the water, read on the burette the 
amount used, and estimate the amount of nitrogenized 
organic matter present. 

Nitrites in water are a strong evidence of decom- 
posed animal matter. 

Tests. Concentrate a quantity of water to one-third 
its bulk. Acidulate with dilute sulphuric acid; add a 
few drops of a potassium iodide solution, and a small 
quantity of a solution of starch. The nitrites present, 
if any, will permit the immediate formation of the blue 
iodide of starch. 

Nitrates will not produce this reaction. 

The inorganic impurities in water are the chlor- 
ides, sulphates or carbonates of magnesium, calcium, 
sodium, or potassium. These salts cause the hardness 
of water. 



If the hardness may be removed by boiling, it is tem- 
porary. If not so removed it is permanent. 

Tests. Cleanse a platinum foil by burning until it 
ceases to color the flame yellow. 

Burn on the foil a portion of the inorganic residue of 
evaporated water. A momentary violet tint appears; 
potassium is present. If yellow, the salt is sodium; if 
orange-red, it is calcium. 

Add to the water a solution of nitrate of silver; if an 
opaque or white cloud appears, chlorine is present, prob- 
ably in combination with the element detected in the 
above test. 

Water may be purified by distillation, by boiling, or 
by filtration. Distilled water is not fit for continued 
use, as it is not properly aerated. 



ANALYSIS OF URINE. 



Chapter V. 

Urine is a solution in water of the products of the 
retrograde metamorphosis of the body, secreted by the 
kidneys. 

Quantity. An adult male in health passes about 
1,000 grains of solids in twenty-four hours, in solution 
in from forty-six to fifty-six ounces of water. 

The normal constituents, and their approximate pro- 
portions, are exhibited in the accompanying table: 



CONSTITUENTS. 



Parts 

Per Thousand 

of Urine. 



Approximate 
Quantity in 24 
Hours in Grains. 



Per Cent. 

-of 

Total Solids. 



Water 

Urea 

Uric Acid 

Hippuric Acid 

Chlorides '. 

Phosphates 

Sulphates 

Kreatinin 

Mucus and Coloring Matter 

Urates . 

Hippurates , 



950.00 

26.20 

1.00 

1.50 

5.00 

2.75 

1.30 

.87 

.39 

1.60 

.75 



550. 

20. 

30. 
100. 

50. 

25. 

18. 
8. 

32. 

15. 



55.0 
2.0 
3.0 

10.0 
5.0 
2.5 
1.8 
.8 
3.2 
1.5 



Color. The color of urine varies from a wine-yellow 
to amber. After the ingestion of large quantities of 
fluids, it is almost colorless. After free perspira- 
tion, when but little water has been taken, it is much 
darker. 

Colorless urine occurs in diabetes, and lactescent urine 
in interstitial nephritis. Dark yellow or light brown 
urine occurs in the initial stages of fevers and during 
their course. 

Dark red urine depends upon the presence of foreign 
substances taken into the system ; and if dark brown or 
black, blood is probably present. 

Green urine is produced by jaundice (biliverdin), and 
sometimes by indican (animal indigo), which also pro- 
duces blue urine. In either case, especially if indican is 
the cause of the discoloration, the urine is alkaline. 

Normal urine should be clear, with a faint white cloud 
of mucus suspended in the center. 

If turbid, heat a small quantity in a test tube. If the 
urine becomes clear, the cloudiness is caused by urates. 
If the cloudiness remains or increases, but will disappear 
on the addition of acetic acid, it is caused by the carbon- 
ates or phosphates. If the cloud remains after the addi- 
tion of acetic acid, then pus, blood or albumen are 
probably the cause of the cloud. 

Odor. The odor of human urine is faintly aromatic 
in health, when first passed. If there is alkaline decom- 
position, it is ammoniacal. If inflammation of the 
bladder is present, it is fetid. 

Food, drinks and medicines often impart odor to the 
urine. 

Reaction. Normal urine is slightly acid when 
passed, because of the excess of organic acids and the 
acid phosphates. Alkaline urine will follow the use of 
the carbonates, acetates or tartrates. If there is disease of 
the bladder, the urine may be alkaline from the decom- 
position of the urea in the urine. Observe whether the 
decomposition oocurred before or occurs after the pas- 
sage of the urine. Strongly acid urine favors the for- 
mation of calculi, and causes irritation of the kidneys 
and bladder, and may induce structural change in those 
organs. 

70 



Specific Gravity. The specific gravity of human 
urine, determined by the urinometer, varies between 
1015 and 1021 when the normal quantity of urine is 
passed. If the quantity passed varies, the specific grav- 
ity varies in inverse ratio. 

In disease, the specific gravity varies from 1003 to 
1010. Low specific gravity is found in diabetes insipidus, 
and in some forms of Bright's disease. High specific 
gravity is found in diabetes mellitus, in lithsemia, and in 
those cases where the water is scanty. 

To determine approximately the total quantity of sol- 
ids passed in 21 hours, multiply the last two figures of 
the specific gravity by the arbitrary number, 1.125, as 
a co-efficient. The product will be the number of grains 
of solids in one ounce of urine. Multiply this by the 
number of ounces passed in 21 hours, and that result 
will be the desired amount. Estimate the percentage of 
the total amount thus obtained, for the amount of any 
single substance desired, from the percentage column 
on page 69. This can only be approximately correct, 
but is often of great assistance. 

Phosphates. Take a five inch test tube three-fourths 
full of urine, and boil: a white cloudiness appears. Fill 
the tube to within one inch of full with the solution of 
potassium hydrate. The cloud deepens. Set to one 
side for twenty minutes ; the sediment settles to the bot- 
tom. If the sediment is half an inch deep, the quantity 
of the phosphates is about right ; if less than half an 
inch, there is too little ; if an inch, there is too much. 

The normal quantity of the phosphates is increased 
after the taking of phosphorus in any form ; after the 
eating of animal food in large quantities ; in many acute 
febrile diseases, and the earthy phosphates are increased 
after disease of the bones, or after nervous excitement 
or exhaustion. They are decreased in all urine of low 
specific gravity, in diseases of the kidneys and heart, in 
brain disorders, and in certain forms of dyspepsia. 
When present in great excess, they will be precipitated 
and form a sediment, especially when the urine is 
alkaline. 

Chlorides. Take a test tube half full of urine. Add 
three drops of nitric acid to prevent the phosphate from 



being precipitated; then add, drop by drop, a few drops 
of the solution of nitrate of silver. If white, cheesy 
globules fall to the bottom, without much cloudiness, 
there are enough of the chlorides. If there is a milky 
cloudiness, with but little curdiness, there is too little of 
the chlorides; if there is only a milky opacity, there is 
a great deficiency of the chlorides. There is no change 
in the appearance of the urine if the chlorides are 
absent. 

The chloride of sodium is an important constituent of 
the animal body, and its excretion should be quite uni- 
form. It is greatly in excess of the potassium chloride 
in human urine. The chlorides are found diminished in 
acute febrile diseases, and their increased diminution 
foretells an increase of the disease, and an increase in 
their quantity indicates improvement. Their absence in- 
dicates a serious condition. They are also diminished 
when there is effusion and dropsy. 

Their sudden reduction in acute rheumatism foretells 
a metastasis to the heart. 

They are increased when much salt is taken ; after 
physical and mental labor ; in diabetes insipidus ; and 
when effusion is relieved by diuresis. 

Sulphates. To a specimen of the urine add five 
drops of hydrochloric acid; then add one-third as much 
of the barium chloride solution as there is urine. If 
there is a milky appearance, with afterward an earthy 
precipitate, there is probably the normal quantity of 
sulphates present. The sulphates of sodium and potas- 
sium are the salts found. 

They are decreased when meat diet is excluded, and 
in the beginning of low fevers. They are increased with 
meat diet; after taking any compounds of sulphur ; and 
in acute fevers, when the urine has a high specific gravity, 
especially in inflammatory diseases of the nervous or 
muscular systems. 

Urea. To a small quantity of the urine add one- 
third as much strong nitric acid ; cool it immediately to 
about fifty degrees, and shake it thoroughly; then let it 
stand for five minutes. If the full normal quantity of 
urea is present, a very few crystals of nitrate of urea 
may be seen floating in the urine or attached to the sides 

72 



of the tube. If more are seen an excess is present. If 
albumen is present, it must be first precipitated and the 
urine filtered. 

To obtain the urea free, concentrate the urine to about 
one-sixth its bulk ; then add an equal quantity of cold 
nitric acid. Treat the crystals with the barium carbon- 
ate solution; dry this product, and extract the urea with 
alcohol. 

Urea constitutes about one-half of the entire solids of 
the urine. It represents the constant tissue change in 
the body, and is the method of elimination of a portion 
of the superfluous nitrogenous food. 

Urea is increased when the diet is largely animal food ; 
after violent muscular action; in the developing stages of 
acute fevers ; in various nervous disorders ; and in some 
cases of diabetes mellitus. It is diminished in structu- 
ral disease of the kidneys ; in many forms of chronic 
disease ; when the diet is exclusively vegetable, and in 
starvation. Its retention in the system produces uraemia. 
It is usually present in excess if the specific gravity is 
high and sugar is absent. 

Uric Acid. To a specimen of urine, add three per 
cent, of its bulk of strong hydrochloric acid, and allow 
the specimen to stand twenty-four hours. The minute 
red crystals of uric acid will be deposited on the bottom 
and sides of the vessel ; darker, or lighter, as the urine 
is dark or light. 

Murexid Test. Moisten some crystals of uric acid 
with nitric acid. Evaporate the product nearly to dry- 
ness ; the residue is a yellowish mass, if there is only a 
small quantity of uric acid; pink or red, if the quantity 
is large. To this, add a few drops of ammonium hy- 
drate. An immediate rich purplish-red color appears 
for a moment, then fades away. 

Uric acid is constantly present in the urine of man, in 
combination with sodium, potassium, and ammonium. 
It varies with the kind of food taken, and in conditions 
of disease. It cannot be found in the urine of infants 
at the breast. It is the commonest ingredient of calculi. 
It is in excess in all fevers, except yellow fever. It is 
doubled in typhus, and in small pox. It is absent often 
when urea is present in large quantities. 

73 



Hippuric Acid. Evaporate from 16 to 20 ounces 
of urine to one ounce, with constant stirring. Cool 
and filter. To the syrupy filtrate, add 15 drops of con- 
centrated hydrochloric acid. Stir well for a short time, 
then treat it with a few ounces of pure ether, contain- 
ing ten per cent, of absolute alcohol. Slowly evaporate 
the etherial solution, and the hippuric acid will crystal- 
ize in the vessel. Uric acid may be precipitated from 
the urine before beginning the separation of the hip- 
puric acid. 

Hippuric acid is present in larger quantities in human 
urine than uric acid, but is so easily soluble that it is 
difficult of separation. It occurs in the largest quantity 
after an exclusively vegetable diet. Cranberries, black- 
berries, and plums increase it. Benzoic acid and balsam 
of Peru, taken as medicines, produce an immediate in- 
crease in the quantity of hippuric acid. It is increased 
in diabetes, in typhus, in chorea, and in most inflamma- 
tory disorders. 

Albumen. Take a specimen of urine in a test tube, 
and boil. A cloudiness forms, like that described as 
phosphates. Add five drops of nitric acid ; the cloud 
does not clear up as with the phosphates, but deepens, 
and finally settles. This is albumen. 

In alkaline urine, the nitric acid reacts upon the car- 
bonates, and produces so much carbonic acid gas as to 
interfere with the test. In these cases, treat the speci- 
men with a few drops of acetic acid, and then boil ; a 
cloud is produced, if albumen is present, which is not 
dissolved by the addition of more acid. If very little 
albumen is present, the above test may not be decisive. 
Pour an inch of strong nitric acid into a clean tube, in- 
cline the tube a little, and carefully allow a few drops of 
the urine to run down the incline and gently diffuse it- 
self on the top of the acid. A brownish-red color is 
then observed at the line of union. Just above this is 
a narrow white cloud, if the least albumen is present, 
the intensity of the cloud depending on the quantity of 
albumen. If much urea or urates are present, the crys- 
tals may form higher up, but will disappear if warmed, 
while the albuminous cloud will not. Do not boil, as 
all albumen will dissolve in boiling: nitric acid. There 



is generally but little urea or urates found where albu- 
men is present, and, for that reason, the specific gravity 
is low, unless sugar is present. 

The quantity of albumen passed may vary from the 
least perceptible quantity, to enough to solidify the en- 
tire quantity of urine passed when precipitated. 

In the tubules of the kidneys, the normal condition 
is one of diffusion. The animal membrane through 
which the diffusion takes place permits the crystalline 
substances (urea, and the normal salts of the urine) to 
pass through with the water of the urine, from the blood, 
but retains the non-cry stalliz able substances (colloids) 
within the blood. If the pressure upon the membrane 
is increased, or the membrane in any place destroyed, 
the albumen may escape with the urine. Albumen is 
not present, then, in normal urine. It is present when- 
ever there is increased blood pressure in the vessels of 
the kidneys (passive hyperemia), in structural diseases 
of the kidneys (nephritis, Bright's disease), when pus 
and blood are passed with the urine, and after the tak- . 
ing of large quantities of egg albumen. 

Sugar. Before testing for sugar, be sure that no 
albumen is present. If it is, precipitate it by the tests 
described, and filter the urine carefully. 

Moore's Test. To a specimen of urine, add one-third 
as much potassium hydrate, and boil. If sugar is pres- 
ent, the mixture will turn yellow, then brownish yellow, 
then brown, then nearly black, depending on the quan- 
tity of sugar present. 

Trommels Test. To a specimen of urine in a test 
tube, add from 20 to 30 drops potassium hydrate solu- 
tion ; then add, drop by drop, a solution of copper sul- 
phate, shaking the mixture after each addition, until the 
white cloud no longer dissolves. Boil the top of the 
mixture ; the blue color changes to yellow, then to red, 
if sugar is present. 

If no sugar is present, a turbid dirty green or grayish 
green mixture is produced. 

Fehling's Test (Modified). Mix in a mortar a 
drachm of pure sulphate of copper, five drachms of 
rochelle salts, and two drachms of pure caustic soda 
(sodium hydrate). 



Take a little of the paste, as large as a small pea, and 
dissolve by boiling in a drachm or two of water in the 
test tube. Add a few drops of the urine, and boil again. 
If sugar is present, the blue color immediately disap- 
pears, and red, or reddish brown, sub-oxide of copper is 
precipitated. If no sugar is present, the blue color 
becomes turbid ; may change to greenish blue, then to a 
grayish green color, easily distinguished from the dis- 
tinct light or dark reddish brown of the sugar specimen. 

With Trommer's and Fehling's tests, an excess of 
uric or hippuric acid, or the urates, will cause a redac- 
tion of the copper oxide much like the sugar. They are 
not always reliable for this reason. 

Boettgeis Test. To a small quantity of urine in a 
test tube, add an equal quantity of sodium carbonate 
solution (1 to 3). To this add a small quantity subni- 
trate of bismuth, and boil for some time. The powder 
turns gray, then brown, then black, according to the 
quantity of sugar present. It is unchanged if sugar is 
absent. This test is very reliable. 

Fermentation Test. Determine the exact specific 
gravity of two specimens of the same urine. To one 
of the specimens add a little yeast and set them both in 
a warm place for 2-i hours, when the specific gravity is 
again taken. The yeast specimen will be found lighter 
than the other. Every degree of specific gravity it has 
lost represents one grain of sugar in each ounce of the 
urine. 

Fit a large test tube or a bottle with a cork through 
which passes a bent glass tube. Put into the vessel a 
small piece of yeast, fill it full of urine and cork it tightly 
with the tube passing nearly to the bottom. Set it in a 
warm place and dip the open end of the tube into an 
empty bottle. As fermentation progresses, every vol- 
ume of gas generated will replace an equal volume of 
urine, which will escape into the empty bottle, and can 
be measured. Every grain of sugar decomposed will 
form 17 cubic centimeters of gas, and replace four 
fluid drachms and 36 minims of the urine. 

Sugar is present in normal urine in too small a quantity 
to be detected by the usual tests. Any quantity so dis- 
covered is abnormal. It is found in large quantities only 



in diabetes mellitis. It appears temporarily in smaller 
quantities after injuries to the brain or central nervous 
structure, or after profound impressions upon the nervous 
system ; in pregnancy, in uterine disease, and in certain 
disorders of the digestion. It is thought to occur fre- 
quently during the course of many severe inflammatory 
disorders and prostrating fevers, and after taking cer- 
tain medicines. 

Its presence is important only when it is more or less 
recurrent or permanent. 

Blood. When blood is found in urine in any quan- 
tity, serum albumen must be present also. If albumen 
is present without blood, the product, coagulated by the 
tests already described, are white. In the application 
of the same tests, if any red blood cells are present, the 
precipitated mass will be discolored from a light brown- 
ish mass to a dark brown or nearly black precipitate, 
according to the quantity of blood present, and the 
urine above the precipitate will become quite clear. 
When the phosphates are precipitated by the method 
described, they will be red or reddish brown, instead of 
their normal color, if blood is present. 

Blood cells may be seen by examining a specimen 
under the microscope. 

Add a few drops of tincture of guaiacum to a little 
urine in a test tube. To this add a mixture of ether and 
per oxide of hydrogen (ozonic ether), and agitate. If 
blood is present the ether will acquire a blue tint. 

*Blood, blood cells, or blood coloring matter may be 
found in the urine from a number of causes. From 
hemorrhage from the capillaries of the parenchyma, as 
a result of intense congestion, or greatly increased blood 
pressure; from severe internal hemorrhages; from traum- 
atism of the kidneys or bladder ; after severe muscular 
exertions or violent strain ; in destructive structural dis- 
ease of the kidneys or bladder, as in acute inflamma- 
tion, and in cancer; often in Bright's disease. And blood 
will be found sometimes persistently in the gouty or 
uric acid diathesis. It is also found after the ingestion 
of certain irritating medicines. 

Pus. Pus is present, if at all, in a sediment. Pour 
the urine from the sediment; add to the sediment a piece 

77 



of caustic soda or potassa, and stir. If pus is present it 
will turn from white to green, and become vitreous, 
denser, and finally an adherent mass. No other sub- 
stance produces this reaction. If only a little pus is 
present it will change to a mucilagenous fluid instead of 
an adherent mass. Pus cells seen under the microscope 
are twice as large as blood corpuscles, and have a gran- 
ular exterior. 

Upon agitation of a specimen of urine containing pus, 
the pus is uniformly diffused through the urine, giving 
it an opaque appearance. It sinks to the bottom quickly 
as a pale yellow or greenish white sediment. If albu- 
men precipitates with the usual tests from the urine with 
the sediment diffused, preserve the precipitate ; allow 
the sediment in the urine to settle; pour off the super- 
natant urine and test it and the sediment separately for 
albumen. Compare the quantity obtained in the three 
tests — medium quantity in the first ; maximum quantity 
in the last ; minimum quantity in the second, if pus is 
present. 

Pus is present in the urine in abscess of the kidneys, 
bladder, or contiguous structures, and sometimes after 
destructive inflammation of these organs. 

The writer observed large quantities of pus persisting 
in a patient with interstitial nephritis, who was an ex- 
cessive cigar and cigarette smoker. The pus would be 
absent if he abstained from smoking for a time, but 
immediately recurred as soon as the smoking was re- 
sumed. 

Mucus is not easily detected in urine. In excess it 
is a colorless deposit, which does not mix readily with 
the urine, but is poured from the vessel like syrup, and 
is ropy or tenacious. 

It may be precipitated with alcohol and tincture of 
iodine, or with acetic acid in a solution of potassium 
iodide. 

It is present in catarrhal conditions of the urinary ap- 
paratus, and sometimes during pregnancy. 

Bile. Add to a specimen of urine one-third its bulk 
of the potassium hydrate solution. Then slowly add 
hydrochloric acid in excess until the alkalinity is entirely 
neutralized. If bile is present the mixture turns to a 



deep emerald green ; if no bile is present it is colorless. 
The color of urine when bile is present varies from a 
dark yellow to brown, and leaves a stain on linen. 

Bile is found in the urine in structural diseases of the 
liver, and at times in temporary disorders of that organ. 

ANIMAL URINE. 

In the analysis of the urine of animals, the student 
must be familiar with all the methods described in the 
analyses of human urine, as the tests in either case are 
the same. 

Man is an omnivorous cmimal, and only differs from 
the beast of that class in habits and intellectuality. 
Because of the influence of the mind, and the superior 
intelligence of man ; because of worry, anxiety, and 
nerve shock; because of physical habits and social cus- 
toms, he is subject to diseases which are not found in 
the lower animals. Yet, all the constitutional diseases 
of these animals have their congeners in the disorders 
of mankind. 

A perfect knowledge of the methods of the analysis 
of urine will render the veterinarian pre-eminently su- 
perior in the ability to diagnose and treat, not only 
kidney diseases, but the constitutional disorders of the 
lower animals. 

Taking into consideration the urine of all animals, 
wild and domestic, we find interesting differences, as 
well as great similarity. All urines are not liquid. 
Many animals, and fowls, have no urinary bladder, the 
ureters opening into the rectum. In these cases, the 
urine is solid. The urine of serpents is a solid mass, vary- 
ing in size from that of a pea to a rounded mass two 
and one-half or three inches in diameter. The urine of 
fowls is solid. Guano is almost exclusively the urine of 
the sea fowl. All insects deposit solid urine. While these 
facts are true, about the only marked differences in these 
urines is the absence of water. If the urine of insects, 
reptiles and fowls be examined in comparison with that 
of domestic animals and man, many of the same con- 
stituents will be found in all. There are many striking 
resemblances. The sodium and potassium phosphates, 
certain ammonium compounds, sodium chloride, urea 

79 



and hippuric acids and their salts are all very common 
constituents. We, however, need study liquid urine 
only. 

The food of animals determines, to a certain extent, 
the character of their urine. The urine of carnivorous 
animals is rather light colored, clear, without sediment, 
has an acid reaction, due to the presence of a large 
quantity of uric acid (which is not found in the urine of 
herbivora), and to phosphoric acid, represented by the 
phosphates. The urine changes as the food changes. 
The urine of many pet dogs presents all the peculiari- 
ties of that of the omnivora. 

The urine of omnivora we have described in our de- 
scription of human urine. The urine of herbivorous 
animals is the darkest of the three, and deposits a sedi- 
ment on cooling. It is strongly alkaline because of the 
carbonates of the alkalies. It contains no uric acid, 
and no phosphates. This fact accounts, to an import- 
ant extent, for its alkalinity, as it is the phosphoric and 
uric acids which causes the acid reaction of other urine. 
Herbivorous urine contains an excess of the carbonates, 
and hippuric acid, which are absent in the urine of car- 
nivorous animals, and present only in small quantity in 
omnivora. The alkaline and earthy phosphates are 
present in large quantities in the urine of carnivorous 
animals. 

While these differences appear in the urine of differ- 
ent animals, we find great variations in the urine of the 
same animal as the quality and quantity of food and 
drink changes ; as he is active or passive ; as he is af- 
fected by the changes in habit, climate, and various 
other influences. 

In quantity, the horse passes from 43 to 56 English 
pints of urine in 24 hours, with a specific gravity vary- 
ing from 1032 to 1050 The specific gravity of the urine 
of cattle ranges from 1032 to 1042 , that of swine, from 
1010 to 1012 ; that of goats and sheep, from 1007 to 
1010. 

There is probably the same relative proportion of 
solids in comparison with the weight of the animals, 
eliminated by all of these animals, but those solids are 
eliminated in a larger or smaller percentage of water. 



In testing animal urine, the same apparatus may be 
used as in the testing of human urine, except that larger 
test tubes (6 inch) should be used. A few important 
differences between the normal and abnormal constitu- 
ents of human and animal urine may be studied. 

Urea, in the urine of horses and cattle, is excreted 
in a larger proportion than in man. If a half test tube 
of urine be treated with one- third its bulk of nitric acid, 
the crystals of nitrate of urea precipitate to one-fourth 
or one-sixth the bulk of the urine, on cooling. The 
urine of the dog is generally quite rich in urea. 

Urea is found in the urine of all animals, and as it rep- 
resents the excess of nutrition, as well as tissue meta- 
morphoses, artificially fed domestic animals are liable to its 
accumulation in the system, resulting in a condition of 
uremic poisoning, with all its influences upon the nerv- 
ous system — spasm, paralysis, dyspnoea, delirium, coma 
and death. 

In the disease in horses known as Azoturia, the symp- 
toms are, to a large extent, those of uremic poisoning. 
At the same time a great excess of urea is found in the 
urine. In the uremic poisoning of man, there is a 
retention of the urea in the blood, there being but very 
little found in the urine. In azoturia, the probabilities 
are that there is an enormous excess in the blood, even 
after the kidneys are doing their very utmost to elimin- 
ate it. That this excess is augmented by immediate 
exercise and rapid tissue waste, and as a result violent 
uremic intoxication suddenly occurs, while the urine is 
loaded with urea. 

Uric Acid is sometimes found in exceedingly small 
quantities in the urine of herbivorous animals, although 
normally absent. It is excessive in the urine of dogs 
and cats, even when these animals are fed upon mixed 
diet. While uric acid is absent from the urine of 
nursing infants, it is found present in tlie urine of suck- 
ing calves. (Wohler.) At the same time hippuric acid 
is entirely absent in the calf, but is present in the infant. 
(Harley.) 

Uric acid calculi are formed in dogs. 

Hippuric acid is the normal acid of the urine of 
herbivorous animals. It is present in the proportion of 



10 or 12 parts per thousand in the urine of horses, and 
absent in carnivora. 

Horses highly fed without exercise pass a much less 
quantity of hippuric acid than when at work, although 
this statement is opposed by good authorities. In mak- 
ing comparisons, it is difficult to estimate all influences. 
In all conditions of imperfect aeration of the blood, 
hippuric acid is found in increased quantities. It is 
a normal constituent of the blood of herbivorous ani- 
mals. 

Chloride of Sodium is essential to the nutrition of 
herbivorous animals. Wild cattle, in some parts of 
Africa, travel hundreds of miles to drink at salt springs. 
It increases the functions of the body, and conduces to 
accumulation of fat and preserves health. Its presence 
in the urine, when not given in excess, is an index to the 
physical condition of the animal. 

Albumen. Inflammation of the parenchyma of the 
kidneys is by no means as common in the lower animals 
as in man, because with man alcohol and tobacco are 
active and common causes. Albumen will be found in 
the urine of animals after hemorrhage into the urinary 
passages from any cause, as from direct injury or violent 
muscular exertion. It is found in the "red water" in 
cattle, because of the presence of blood serum and 
broken down blood corpuscles. It occurs after injury 
to, or diseases of, the brain or spinal cord, and from 
the absorption of certain irritating substances into the 
blood, such as turpentine, cantharides, etc. If actual 
inflammation of the kidneys does occur, the pathology is 
the same as in human urine, with the constant presence 
of albumen. 

Mucus and Pus. These substances are found in 
larger quantities, proportionately, in the urine of ani- 
mals than in that of man, and may be recognized by the 
same tests. 

The mucus lining of the pelves of the kidneys, or of 
the ureters, bladder and urethra, may deposit very large 
quantities of clear, transparent ropy mucus. Mucus 
from the vagina is often found in the urine after partu- 
rition. Mucus in excess will sometimes be found in the 
urine of horses after violent muscular exertion. 



Pus is found when there is excessive irritation of the 
urinary apparatus, or after inflammation of these parts 
as described. 

Carbonates. — The carbonates of the alkalies potas- 
sium, sodium, and ammonium, are soluble in water, and 
do not readily precipitate; but the earthy carbonates are 
quite insoluble, and the carbonate of calcium will pre- 
cipitate from the urine of the horse, in health, a short 
time after it has been passed, in the form of an earthy 
powder or chalky sediment. It decomposes readily upon 
the addition of the mineral acids, giving off large quan- 
tities of carbonic acid gas. (C0 2 ). 

For this reason acetic acid should oe used in these 
tests instead of nitric acid. 

Ordinary calculi in the horse are largely formed of this 
substance. 

In calcareous degeneration, or ossification of a part or 
organ in the animal body, the deposit is largely of the 
carbonate of lime, which in these cases is in excess in the 
blood 

Phosphates. — The phosphates are not normally pres- 
ent in any appreciable quantity in the urine of herbivor- 
ous animals. 

But certain foods will cause their appearance in large 
quantities, when they may be precipitated upon the mu- 
cous surfaces of the bladder and urethra, or upon the 
external parts. Their presence gives rise to irritation of 
the bladder and urethra, and may lead to an inflamma- 
tion of those organs and the kidneys. They are found 
in excess also in certain inflammatory diseases, either of 
an acute or chronic character. 

Oxalic Acid. — This substance is more often found 
in the urine of domestic animals than in man. It is 
deposited in the form of the insoluble oxalate of lime, 
when those substances are eaten which contain oxalic 
acid in abundance, or when from any cause there is a 
fault in tissue metamorphosis — when the waste products 
are not properly converted into urea. The formation of 
oxalic acid within the body seems to be an intermediate 
stage of tissue change, m the process of the conversion 
of nitrogenous effete matter into urea, which occupies 
the highest position m the scale. The process of change 



being interfered with, the oxalic acid remains, and is 
converted into soluble and Insoluble oxalates. 

Tests. — If oxalic acid is suspected in the urine, the 
addition of acetic acid to urine containing the carbonate 
of lime will allow the characteristic crystals of calcium 
oxalate to precipitate alone. If the lime salts are not 
present, a solution of calcium chloride may be added 
after the acetic acid, which only serves to prevent phos- 
phates from being precipitated. These crystals are in- 
soluble in water, liquor potassa, or acetic acid, but will 
dissolve immediately in nitric acid without effervescence. 
Familiarity with the microscopical appearance of the 
crystals is essential. They assume four distinct forms : 
The regular octohedra, the dumb-bell, the irregular disc, 
and the diamond-shaped crystals. 

There is not much danger of mistaking them, as only 
tri-calcium phosphate and uric acid is likely to be pre- 
cipitated under the same circumstances, and with these 
we are familiar. 

Sugar is not common in the urine of herbivorous ani- 
mals. They are not often subject to diabetes mellitus ; 
but dogs and other omnivorous animals will excrete 
sugar in large quantities under certain circumstances. 
The tests are the same as in human urine. 



INDEX. 



ABSOLUTE ALCOHOL,46. 
Absolute weight, 3, 
Acetic acid, 47. 
Acetous fermentation, 47. 
Acetyl hydrate, 47. 
Acids, definition of, 9. 

Structure of, 8. 

Arsenious, 27. 

Hippuric, 73. 

Hydrofluoric, 22. 

Hydriodic, 26. 

Hydrocyanic, 60. 

Hydrobromic, 25. 

Hydrochloric, 23. 

Nitric, 20. 

Nordhausen, 32. 

Oxalic, 61. 

Prussic, 60. 

Sulphovinic, 48. 

Sulphurous, 30. 

Sulphuric, 31. 

Uric, 73. 
Air, 17. 
Albumen in Urine, 74. 

In Animal Urine, 82. 
Alcohol, 46. 
Alkahimides, 10. 
Amides, 10. 
Amines, 10. 
Ammonia, 18. 
Ammonium Compounds, 19. 

Bromide, 20. 

Carbonate, 19. 

Chloride, 19. 

Bydrate, 19. 

Iixlide, 20. 

Nitrate, 19. 

Sulphate, 19. 
Ampere's Law, 10. 
Amorphous Carbon, 43. 
Analytical Chemistry, 51. 
Analysis (if I 'line, 69. 
Animal Charcoal, 43. 
Animal Urine, 79. 
Antimony, 28. 

Tests for, 64. 



Antozone, 14. 
Apparatus, 51. 
Apparent "Weight, 3. 
Aquafortis, 20. 
Arsenic, 27. 
Arsenic, Tests for, 61. 
Arsenious Oxide, 27. 
Atom, 5. 

Atomic Weight, 5. 
Atmosphere, 17. 
Attractions of Matter, 3. 
Atropine, Tests for, 59. 
Aurum, 40. 
Azote, 16. 

BASES, definition of, 9. 
Structure of, 8. 
BerthoTet's Law, 52. 
Bile in Urine, 78. 
Binary Molecules, 7. 
Bismuth, 41. 

Subnitrate, 41. 
Bittern, 25. 
Black lead, 43. 
Blende, 29. 
Blood in Urine, 77. 
Bone Black, 43. 
Bromine, 23. 
Bromoform, 49. 

CADMIUM, 38. 
Calcium, 35. 
Calomel, 42. 
Carbo-animalis, 43. 
Carbo-ligni, 43. 
Carbon, 42. 

Dioxide, 42. 
Carbonic Acid Gas, 44. 
Carbonous Oxide, 44. 
Carbon Plates, 44. 
('ail urn Points, 44. 
Carbonates in Animal Urine, 

83. 
Charcoal, 43. 

Chemistry, Definition of, 2. 
Chemism, 3. 



Chemical Elements (Table), 4. 
Chemical Solution, 52. 
Chlorine, 22. 
Chloride of Gold, 40. < 

Of Gold and Sodium, 40. 

Of Sodium, 24. 

Of Sodium in Animal 
Urine, 82. 
Chlorides in Urine, 71. 
Chloroform, 48. 
Coal, 43. 
Cobalt, 39. 
Cohesion, 3. 
Coin Silver, 39. 
Coke, 43. 
Common Salt, 24. 
Compound, A, 5. 

Molecule, A, 6. 
Copper, 37, 
Cryolite, 22. 
Cuprum, 37. 

DECANTATION,53. 
Desiccation, 53 
Diamond, 53. 
Diffusion, 17. 
Dilute Alcohol, 47. 
Dioxide of Carbon, 44. 
Distillation, 53. 
Di-sulphuric acid, 32. 

ELECTKO-CHEMISM, 7. 
Elements, 5. 
Ether, 48. 
Ethyl Oxide, 48. 
Equivalence, 6. 
Evaporation, 53. 

FERMENTATION, 46. 
Eiltration, 53. 
Fluorine, 22. 
Fluoroform, 49. 
Eluor Spar, 22. 
Formula, Definition of a, 7. 
Formyl Iodide, 49. 
Fusion, 52. 

GALENA, 29. 
Gas, 3. 
Gas Retort Carbon, 43. 
General States of Matter, 3. 

"Working Rules, 54. 
Glycerine, 50. 
Gold, 40. 

Graham's Law, 18. 
Graphite, 43. 
Gravitation, 3. 



HALOGENS, THE, 22. 
Haloid Salts, 22. 
Hippuric Acid, 74. 

In Animal Urine, 81. 
Hydrocarbons, 48. 
Hydrocyanic Acid, Tests f or,60 
Hydrobromic Acid, 25. 
Hydrochloric Acid, 23. 
Hydrofluoric Acid, 22. 
Hydriodic Acid, 26. 
Hydrogen, 12. 

Bromide, 25. 

Per Oxide, 13. 

Sulphate, 31, 

Sulphite, 29. 
Hyponitrous Oxide, 20. 

INCINERATION, 53, 
1 Indestructibility of Mat- 
ter, 3. 
Inorganic Chemistry, 2. 
Iodine, 26. 

Iodide of Mercury. 42. 
Iodoform, 49. 
Iron of Leonarto, 12. 
Isomorphism, 22. 
Ivory Black, 43. 



J 



ET, 43. 



T^UPFERNICKEL, 38. 

LABORATORY COURSE 
51. 
Laughing Gas, 20. 
Lead, Tests for, 65 
Linking Elements, 8. 
Liquids, 3. 

MAGNESIUM, 35. 
Mass, 2. 
Matter, 2, 

Mercuric Chloride, 42. 
Mercurous Chloride, 42. 
Mercuric Iodide, 42. 
Mercurous Iodide, 42. 
Mercury, 41. 

Test for, 66. 
Mild Chloride, 42. 
Mispickle, 27. 
Molecules, 6. 
Monoxide of Carbon, 44. 
Morphine, Tests for, 58. 
Mother of Vinegar, 47. 
Mucus in Urine, 78. 
In Animal Urine, 82. 



Mycoderrua Aceti, 46. 

'AMINGof COMPOUNDS, 



N' 



Ternary Compounds, 9. 
Nascent State, The, 13. 
Natrium, 34, 
Natural Science, 2. 
Nickel, 38. 
Nitric Acid, 20 
Nitrogen, 16. 
Nordhausen Acid, 32. 

OIL OP VITRIOL, 31. 
Organic Chemistry, 42. 
Organic Substances, 46. 
Orpiment, 27. 
Oxalic Acid, Tests for, 61. 
In Animal Urine, 83. 
Oxygen, 13. 
Ozone, 14. 

PARAFFINE SERIES, 48. 
Pencillium Glaucum, 46. 
Peroxide of Hydrogen, 15. 
Phenol, 50 
Phosphorus, 33 

Tests for, 67. 
Phosphates in Urine, 71. 
Physical Science, 2. 
Physics and Chemistry, 2. 
Plastic Sulphur, 29, 
Platinum, 43. 
Plumbago, 43. 
Poison, 56. 

Polythionic Series, 31 
Potassium, 34. 

Carbonate, 34; 

Hydrate, 34. 

Nitrate, 34. 
Preliminary Work, 54. 
1 'i ussic Acid, Tests for, 59. 
Pus in Urine, 77. 

In Animal Urine, 82. 
Pyroligneous Acid, 47. 



Q 



UICKSILVER, 41. 



RADICAL, A, 10. 
l!c;iction, 52. 
Reagent, 62. 

SALTS, 8. 
Definition of, 9. 



Science, 2. 
Silver, 39. 

Simple Molecule, 6. 
Simple Solution, 52. 
Sodium, 34. 

Chloride, 24. 
Solvent, 52. 
Specific Weight, 3. 
Stannum, 39. 
Stibnite, 28. 
Stoichometry, 11. 
Strychnine, Tests for, 57. 
Sublimation, 53. 
Sugar in Urine, 75. 

In Animal Urine, 84. 
Sulphovinic Acid, 48. 
Sulphates in Urine, 72. 
Sulphur, 28. 
Sulphuric Acid, 31. 

Ether, 48. 
Sulphuretted Hydrogen, 29. 
Sulphurous Oxide, 29. 
Symbol, 5. 

TARTAR EMETIC, 28. 
Ternary Molecules, 7. 
Theoretical Chemistry, 1. 
Tin, 39. 

Torula Cerevisise, 46.. 
Toxicology, 56. 
Tri-oxide of Arsenic, 27. 

UREA, 72. 
In Animal Urine, 81. 
Uric Acid, 73. 

In Animal Urine, 81. 
Urine, Human, 69. 
Of Animals, 79. 

VINEGAR, 47. 
Vinic Alcohol, 46. 

WATER, 15. 
Water Type, 8. 
Water, Tests for Impuriti 

in, 68. 
Weight, 3. 
White Arsenic, 27. 

ZINC, 38. 
Carbonate, 38. 
Oxide, 38. 



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